ISO/TR 25078:2025

Technical
Report
ISO/TR 25078
First edition
Wood and wood-based products —
2025-05
Examples of calculating
displacement potentials for wood-
based products and considerations
for further analyses
Bois et produits à base de bois — Exemples de calcul des
potentiels de déplacement pour les produits à base de bois et
considérations pour d'autres analyses
Reference number
© ISO 2025
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Establishing alternative products . 1
5 Establishing displacement factors for wood-based products. 2
5.1 General .2
5.2 Types of data sources .4
5.3 Calculation approaches to determine value chain emissions of wood-based and
alternative products .5
5.4 Calculation examples, including data sources .5
5.4.1 Example 1 – Wooden pallet vs. Plastic pallet .5
5.4.2 Example 2 – Wood-based bioenergy displacing fossil energy sources .6
5.4.3 Example 3 – Cross-laminated timber (CLT) floor to displace concrete floor. .7
5.4.4 Example 4 - Packaging of beverages .8
5.4.5 Example 5 - Building structure .8
5.5 Literature review .10
6 Examples of tier 1 displacement factors for selected products and product categories .12
7 Factors that can influence realisation of displacement potential . 14
7.1 General .14
7.2 Market effects .14
7.3 The time dimension. 15
7.4 Biases and choice of product system . 15
Bibliography . 17

iii
Foreword
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The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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This document was prepared by Technical Committee ISO/TC 287, Sustainable processes for wood and wood-
based products.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
ISO 13391-1 defines a framework for calculating greenhouse gas dynamics of wood and wood-based products,
see Figure 1. The framework identifies the displacement potential relating to displacing alternative products
by using wood and wood-based products. This includes quantification of the value chain emissions of both
the wood-based product and the alternative product, as shown in Figure 1. Displacement is composed of two
parts, the greenhouse gas emissions related to the wood-based product(s) and the potentially prevented
greenhouse gas emissions related to the alternative product(s), see Figure 1.
ISO 13391-1 provides calculation guidance for all aspects of the greenhouse gas emissions related to the
wood-based product’s value chain. ISO 13391-3 considers the emissions of alternative products and further
elaborates on the calculation of displacement potentials. This document provides additional background and
examples to users of ISO 13391-1 and ISO 13391-3. It includes aspects of the calculations as such, and also
the wider context of analysing factors that can affect to what extent the displacement potential is realised.
Figure 1 — Illustration of the components of the greenhouse gas dynamics of wood and wood-based
products
This document provides background and examples in the following areas:
— Clause 4: Approaches for identifying alternative products, i.e. products with similar functionality but
with different material origins that can be displaced by wood-based products. This pairing of alternatives
is a basis for the calculation of displacement potentials.
— Clause 5: Examples of how to establish displacement factors, i.e. the quantity of greenhouse gas
emissions avoided through displacement (in carbon dioxide equivalents) per unit of biogenic carbon (in
carbon dioxide equivalents) contained in the wood-based product(s). The displacement factors are thus
expressed in t CO e/t CO e and are as such unitless.
2 2
— Clause 6: Examples of tier 1 displacement factors for broad product categories based on the literature.
— Clause 7: Review of factors that can influence realisation of displacement potentials in society, including
the development of the wider economy and consumption patterns.

v
Technical Report ISO/TR 25078:2025(en)
Wood and wood-based products — Examples of calculating
displacement potentials for wood-based products and
considerations for further analyses
1 Scope
This document provides examples and background literature for identifying and calculating greenhouse gas
displacement potential for wood-based products as defined in ISO 13391-3:2025, including the calculation of
displacement factors.
This document also provides a review of considerations for further analyses that address the impact of these
potentials over time in a broader economy setting.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 13391-1:2025, Wood and wood-based products — Greenhouse gas dynamics — Part 1: Framework for value
chain calculations
ISO 13391-3:2025, Wood and wood-based products — Greenhouse gas dynamics — Part 3: Displacement of
greenhouse gas emissions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13391-1 and ISO 13391-3 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Establishing alternative products
Defining the functional unit is fundamental when calculating displacement factors and working with value
chain emissions estimates for alternative products. This is in order to allow for an objective comparison
between the alternative product and the wood or wood-based product. As per ISO 14040:2006, a
functional unit is defined as the “quantified performance of a product system for use as a reference unit”.
It is best practice to apply expert judgement when establishing the alternative product to ensure functional
equivalence. However, it is important to recognize that a specific material can fulfil more than one function.
For instance, in the case of a concrete shear wall, the wall provides structural capacity, a barrier to sound
transmission, as well as fire protection. In comparison, a wood-framed wall might only provide structural
capacity, and additional materials such as acoustic insulation and gypsum board are needed to meet the
sound transmission and fire protection requirements, respectively. Therefore, when establishing the
alternative product to a wood-based product to evaluate the displacement potential, it is best practice to
examine the functional unit from a system perspective.
Functional units for construction products can be based on building components providing a specific
function (e.g. 9 m × 9 m floor plate that supports an office space) or a complete building system (e.g. 4-storey

residential building). A life cycle assessment (LCA) can then be performed to determine the emissions of
both the wood-based product and alternative options in order to determine the displacement potential.
Environmental Product Declarations (EPD) can be used to perform the assessment. However, a direct
comparison of the EPD results between the wood-based product and an alternative product can only be
performed when the EPD is based on the same declared unit with functional equivalency, and the conditions
for comparing EPDs in ISO 14025 are met.
Similarities between the wood-based product and the alternative product can be defined to simplify the
analysis. For instance, when the functional unit is defined as a building, it can sometimes be assumed
that the operational energy use for the wood building is the same as the operational energy use for the
alternative (e.g. concrete or steel) building. Similarly, the scope of the functional unit can be defined to
simplify the comparison, for example limiting the functional unit to just the superstructure of the building.
This approach would not capture the impact of the mass of the superstructure in the foundation design,
but the results of the study can be more broadly applied if repeatable construction is being considered e.g.
where the building structure is being repeatedly constructed in multiple locations.
It is also important to account for the geographical location where the alternative product is manufactured
and used. The energy production system, technological efficiency, and electrical grid will all impact the
emissions of the manufacturing, use, and end of life stages of the wood-based and alternative product.
Emissions will also reflect the geographically relevant manufacturing processes, use conditions, and end of
life processes.
Equivalence between the system boundary of the alternative product and the system boundary of the
wood-based product is necessary to ensure consistency for the comparison. A comprehensive study would
consider the full life cycle, including raw material extraction, processing, transportation, manufacturing,
distribution, use, re-use, maintenance, replacement, and final disposal. This approach is often referred to as
‘cradle-to-grave’. Another commonly used approach is ‘cradle-to-gate’ and can be selected where only the
stages up to the end of manufacture are currently available. Establishing the processes for life cycle stages
beyond the manufacturing gate will require assumptions, and there will therefore be inherent uncertainties
in the study and reduce the representativeness of the results. Additionally, since there is no guarantee of
the exact destiny of the product, providing a description of each plausible scenario in a report provides
transparency about the analysis, the assumptions and the results.
An evaluation of the products that are readily available on the market and commonly used to perform the
required function within the defined temporal boundary assists in establishing the alternative product. It is
entirely possible that a single wood-based product can displace several other products, so a representative
set of alternative products would then be selected. It is equally possible that some wood-based products do
not displace any other products at all, for example where the wood-based product is the market leader or
default choice for a given application, e.g. paper within books. It would be possible to compare a printed book
with an e-reader, but at this current time the e-reader is not the item being displaced, it is in fact displacing
the book.
Many studies are careful to do this based not only on functional equivalence, but also market share of the
various alternative products, i.e. assigning factors based on the proportion of the various products that can
be displaced by the wood-based product.
5 Establishing displacement factors for wood-based products
5.1 General
Clause 5 provides calculation examples for the establishment of displacement factors based on the literature.
It includes consideration of greenhouse gas emissions in the wood-based product(s) value chain as well as
the emissions from alternative products.
NOTE 1 'Emissions from alternative products' is a term defined in ISO 13391-1.
This document also deals with situations that do not lead to displacement.

As per ISO 13391-3, the displacement factor for a specific use of wood-based product(s) is calculated as given
in Formula (1):
mm−
Ea,,pE w
f = (1)
Ds, pec
ww−
Bw,,Bap
where
f
is the displacement factor for a specific use of the wood-based product in a specific geographical
Ds, pec
scale, expressed in t CO e/t CO e;
2 2
m
is the quantity of emissions from alternative products with functional equivalence to the wood-
Ea, p
based product considered, expressed in t CO e;
m
is the greenhouse gas emissions related to the wood-based product considered, expressed in t CO e;
Ew,
w
is the quantity of biogenic carbon in the wood-based product placed on the market in the specified
Bw,
time period, expressed in t CO e;
w
is the quantity of biogenic carbon in the alternative product, expressed in t CO e.
Ba, p
[44]
NOTE 2 Formula 1 is the equivalent of a widely recognized formula used in e.g. Sathre and O’Connor, but the
symbols have been re-drafted in accordance with ISO drafting rules.
Two other useful formulae from ISO 13391-1 is for converting wood volume to carbon dioxide equivalents in
two steps.
The mass of wood at dry condition can be calculated using Formula 2:
ρ ×V
ωω
m = (2)
dry
ω
1+
m is the mass of wood at oven dry condition (moisture content of 0 %)
dry
ω is the gravimetric moisture content of wood (e.g. 12 % mass of water per mass of dry wood);
ρ is the density of wood at moisture content of ω;
ω
V is the volume of wood at moisture content of ω;
ω
The biogenic carbon content in wood can be calculated using Formula 3:
ww=× ×m (3)
BC,f,drydry
where
w is the biogenic carbon in wood expressed in carbon dioxide equivalents (CO e);
B 2
44 is the molecular mass ratio of CO /C;
w is the carbon fraction in wood at oven dry condition, 0,5 as the default value.
C,f,dry
ISO 13391-3 further details how displacement factors are calculated for sets of wood-based products,
divided into first use (including recycled material) and final use (recovery for energy purposes). This clause,
however, only deals with examples of calculating displacement factors for specific use(s) of wood-based
product(s).
ISO 13391-3 requires that data sources and displacement factors used in calculations are transparently
documented, including the alternative product(s) and product system(s) used with justification.

Determining displacement factors for specific uses can be complicated and depends on consideration of a
range of factors including:
— ISO 13391-3, requires that the functional unit is based on the intended function or service of the product
and defined as the quantified performance of a product system in terms of its unit, magnitude, and if
relevant, duration, reuse, and level of quality;
— ISO 13391-3, recommends that system boundaries suitable for conducting the life cycle assessment (LCA)
of the wood-based product are defined. It is required that the system boundaries, including choices made,
are transparently documented and justified;
— Displacement factors can vary with geographical location depending on variations of greenhouse gas
emissions in both of the compared product's value chains for a specified functional unit;
— Calculations can refer to comparable parts in the value chain where the system boundary is defined
equivalently. The starting point is the “cradle” to account for all upstream emissions. The “gate”,
representing delivery of the product(s) to the customer is often used as the other boundary, under the
assumption that emissions further downstream are of similar magnitudes for the alternative products.
A “cradle-to-grave” boundary can therefore be more accurate for determining the displacement factor
so as to account for the entire value chain in the comparison, although data for downstream emissions of
reasonable quality and comparability can be difficult to obtain;
— Wood-based value chains are complex and integrated. While displacement factors for individual
products at the consumer end can be straightforward to calculate, the displacement factors of products
in the upstream value chain (e.g. sawn wood, wood-based panels, paper, wood pulp, wood-based
energy products and roundwood) requires aggregations and weighting of downstream product mixes,
depending on the set of identified alternatives.
5.2 Types of data sources
Calculation of displacement factors builds on documented data from different types of publications,
including:
— Published scientific articles, including both review articles and articles addressing specific topics, such
as housing construction, that have been published over the past 20+ years.
— The level of data detail can be lower than for LCA studies as the study in question can address a
broader question where displacement factors are only a part.
— As the literature is not standardized in the way that LCA studies are, it can be challenging to extract
data that correspond with the applied system boundary. Analyses are not always documented to
make the extraction of the relevant data possible, which can lead to excluding a study for data quality
reasons.
— Comparative life cycle assessments (LCAs).
— LCAs include standardized approaches to calculate and compare performances of products, see
for example ISO 14044. This provides a good foundation for extracting data for calculation of
displacement factors.
— LCAs can address very specific products in specific market contexts which can make it difficult to
generalize the findings. For example, the alternative product(s) chosen are not always representative
for the overall market, in which case the displacement factor would also not be representative.

— In situations where several LCAs are available for comparing the wood-based product(s) to
alternatives, an approach for utilizing the full set of information is to calculate a weighted mean or
median of specific-use displacement factors across the studies.
— Life cycle assessments and environmental product declarations (EPDs).
— Where no comparative LCA is available it can be possible to obtain the required information for
the wood-based product or the alternative product directly from individual LCAs or EPDs. This is
considered further in 5.3.
5.3 Calculation approaches to determine value chain emissions of wood-based and
alternative products
This clause builds on establishing a functional unit for the products or product systems that are to be
compared, see Clause 4.
The greenhouse gas emissions for the wood-based product, and all identified alternative products, can be
determined using EPDs or LCAs. In addition to the functional equivalence, the relevant geographical region
and energy mix are important as they can have different global warming potential depending on the location
of manufacture, the process efficiencies at the particular factory and other factors. The more specific the
data is (e.g. facility-specific, process specific, region specific, etc.), the more accurate the results will be. If
EPDs or LCA data are not provided on a granular scale, national databases that provide average emission
factors for products can be referenced.
5.4 Calculation examples, including data sources
5.4.1 Example 1 – Wooden pallet vs. Plastic pallet
Case 1:
Based on a global review of published EPDs, two pallet EPDs were found from the same manufacturer,
[45][46]
one for wooden pallets and one for plastic pallets. These studies used the same system boundary,
regional data and functional unit i.e. one loop usage of the plastic or wooden pallet (1 200 × 800 mm) in the
system. The greenhouse gas emissions were reported to be 0,294 kg CO e and 0,478 kg CO e for the wooden
2 2
and plastic pallet, respectively. The amount of solid wood used in the functional unit of wooden pallet is
estimated at 1,04 kg. Following the formula in ISO 13391-3 for determining the biogenic carbon content, the
w is calculated here (assuming pallet wood with a moisture content of 20 %):
B,w
44 10, 4
w = × 0,5 × = 1,589 kg CO e
Bw, 2
12 12+ 0%
There is no biogenic carbon content in the plastic pallet, thus w = 0;
Ba, p
Then using the formula for f :
Ds, pec
mm−
0,,478−0 294
Ea,,pE w
f = = =01, 2
Ds, pec
ww− 1,589−0
Bw,,Bap
Case 2:
[16]
Deviatkin and Horttanainen compare the carbon footprint of EUR-sized wooden and plastic pallets,
taking into account a wide range of factors for the functional unit, including number of re-use rounds and
repairs. The functional unit was set to 1 000 utilizations. The greenhouse gas emissions for the plastic pallet
was 15 × 62 = 939 kg CO e (15 pallets needed for the functional unit). Biogenic carbon content of the wooden
pallet (50 pallets needed for the functional unit) was 50 × 36,0 = 1 798 kg CO e, including material for
repairs. The greenhouse gas emissions for the wooden pallet functional unit (cradle-to-gate) was 50 × 5,0 =
250 kg CO e. Calculations refer to first use and do not include displacement at final use for energy.
mm−
Ea,,pE w 939−250
f = = =03, 8
Ds, pec
ww− 1798−0
Bw,,Bap
Table 1 — Calculated displacement factor (f ) for first use of wooden pallet based on
D
References [16][45][46]
w m , m , Calculated f
Displaced
B,w E w E ap D
Pallets
product
kg CO e/FU kg CO e/FU kg CO e/FU t CO e/t CO e
2 2 2 2 2
Case 1: Wooden pallet 1,589 0,294 Plastic pallet 0,478 0,12
Case 2: Wooden pallet 1 798 250 Plastic pallet 939 0,38
These two cases in Table 1 demonstrate how a simple change in functional unit can lead to a large difference
in the displacement factor value obtained.
5.4.2 Example 2 – Wood-based bioenergy displacing fossil energy sources
Wood-based bioenergy can displace different forms of fossil-based energy, thereby displacing greenhouse
gas emissions. The displacement factor will vary depending on the alternative fossil energy source, and the
efficiency in energy production and delivery in both the wood-based and the fossil-based system considered.
Energy production is relatively well investigated, which means that emission factors for a variety of systems
are available, including for electricity only, heat only, or combined heat and power production (CHP). Among
fossil-based energy sources, and compared with oil combustion, coal combustion generates higher relative
greenhouse gas emissions and natural gas lower relative greenhouse gas emissions. This means that the
displacement factor is higher when biomass replaces coal, and lower when biomass replaces natural gas.
When wood-based electricity (for example as part of the output from a CHP facility) displaces alternative
electricity production for the grid, assigning an emission factor for the alternative production becomes
significant. For example, in a European context, there will be a large difference between the average
emissions from electricity production (“the European mix”), compared with high-emission production
from coal-fired plants on the margin of the European grid. Either of these assignments can be valid for the
calculations at hand but will lead to different results. See also 7.4 for further elaboration on this topic.
Case 1:
[43][37]
Based on the published research papers , LCA studies were performed to determine the greenhouse gas
emissions factors for heating with wood pellet and heating with anthracite coal. The greenhouse gas emission
factors were determined to be 37 kg CO e/GJ, and 103 kg CO e/GJ for the wood pellets and anthracite coal
2 2
respectively. Based on the estimation of oven dry wood heating value of 19 MJ/kg, it will require 52,63 kg of
wood to produce 1 GJ of heating. The biogenic carbon content in wood pellets is calculated as
w = 52,63 ×0,5 × (44/12) = 96,58 kg CO
B,w 2
Then the displacement factor of wood pellet heating to displace coal heating is
mm−
Ea,,pE w 103−37
f = = =06, 8
Ds, pec
ww− 96,58−0
Bw,,Bap
Case 2:
[13]
Cintas et al published a study on the impacts of increased bioenergy production in Sweden, including
impacts on the forest. As part of the calculations, emissions in modern CHP facilities were compared between
biomass sourced from side streams of forest harvesting, natural gas and coal, taking into account conversion
efficiencies and supply chain emission factors. Details of the calculations are found in the referenced article.
For biomass replacing coal, the displacement factor was calculated to 1,27 t CO e/t CO e and for biomass
2 2
replacing natural gas 0,55 t CO e/t CO e.
2 2
Table 2 compares the three results above.
[13] [37] [43]
Table 2 — Calculated displacement factors for wood-based bioenergy based on , ,
w m , m , Calculated f
B,w E w E ap D
Bioenergy Displaced product
kg CO e/FU kg CO e/FU kg CO e/FU t CO e/t CO e
2 2 2 2 2
Case 1: Wood
96,58 37 Coal-based heating 103 0,68
pellets
Case 2: Biomass in
Coal 1,27
CHP facility
Case 2: Biomass in
Natural gas 0,55
CHP facility
5.4.3 Example 3 – Cross-laminated timber (CLT) floor to displace concrete floor.
A typical floor slab designed for mass timber building in the US, following the International Building
Code (IBC) 2021 normally contains 5-ply CLT panel (180 mm-thick) with 7,9 mm-thick (5/16”) sound mat
for acoustic control and 50,8 mm-thick (2”) gypcrete on top for vibration control, see Figure 2 (left). The
displaced functionally equivalent concrete floor slab using reinforced concrete as the main structural
material contains 5 000 psi concrete with a rebar density of 18,8 kg/m (1,75 kg/sq ft) and post tension
cable intensity of 8,6 kg/m (0,8 kg/sq ft).
Figure 2 shows the two flooring slabs.
Figure 2 — 1 m floor system for cross-laminated-timber (left) and concrete (right)
Using these product systems, a specific cradle-to-gate LCA was conducted on the two systems to estimate
the greenhouse gas emissions based on the systems’ value chains.
The greenhouse gas emissions from the product stage of the two floor systems show:
For the CLT floor: m = 49,1 kg CO e/m
E,w 2
For the concrete floor: m = 258,9 kg CO e/m
E,ap 2
The biogenic carbon content in the CLT floor is calculated as:
500kg
 
0,m17461××m
 
()V × ρ
44 44
 
m
w = × 0,5 × = x 0,5 ×
Bw,
12 1+ω % 12 11+ 5 %
() ()
= 146,7 kg CO e
w =0
Ba, p
Then the displacement factor for this case is:
mm−
Ea,,pE w 258,,94− 91
f = = =14, 3
Ds, pec
ww− 146,70−
Bw,,Bap
The results are summarized in Table 3.
Table 3 — Calculated displacement factor for cross-laminated timber (CLT) floor
w m , m , Calculated f
B,w E w E ap D
Flooring Displaced product
kg CO e/FU kg CO e/FU kg CO e/FU t CO e/t CO e
2 2 2 2 2
Cross-laminated
146,7 49,1 Concrete flooring 258,9 1,43
flooring
5.4.4 Example 4 - Packaging of beverages
The Swedish alcohol beverage monopoly commissioned a comparative LCA of different packaging solutions
[20]
for wine. The three comparisons in Table 4 have been extracted from the study as an illustration.
Numbers represent the functional unit (FU) of 1 l of packaged beverage.
Calculated displacement factors were high especially when the alternative product is glass bottles, even
though 83 % of the glass material was recycled. Both energy intensive production of glass bottles and higher
mass in transport contributed to the results.
[20]
Table 4 — Calculated displacement factors for packaging of beverages based on
w m , m , Calculated f
Paper packaging
B,w E w E ap D
Displaced product
product
kg CO e/FU kg CO e/FU kg CO e/FU t CO e/t CO e
2 2 2 2 2
3 l carton box 0,088 0,069 0,75 l glass bottles 0,609 6,2
1 l paper container 0,054 0,053 0,75 l PET bottle 0,253 3,3
1 l paper container 0,054 0,053 0,75 l glass bottles 0,609 9,9
5.4.5 Example 5 - Building structure
Mass timber (such as cross laminated timber [CLT] and glulam) is substituting concrete and steel structures
with impressive speed for new building designs and constructions. An exponential increase of mass timber
[55] [32]
projects has been recorded within the US in the past 10 years. In one case, three functional equivalent
building systems - mass timber, concrete and steel, complied to the 2024 IBC building code and US regional
specification. The total greenhouse gas emissions of the three are quantified for the cradle-to-grave (end
of building life) system boundary. The functional unit is the 12-story residential building with gross floor
area of 12 900 m , and service life of 75 years. The primary structure, including substructure as foundation
system and superstructure like floors, roofs, beams, etc, and enclosures, fire and acoustic assemblies are all
included in the quantification of the whole building greenhouse gas emissions. Only the concrete and mass
timber data are used here to show the calculation of the displacement factor in the whole building level. The
two building systems are shown in Figure 3.

Figure 3 — Two functional equivalent buildings designed for mass timber (left) and concrete (right)
structural systems
The total GWP impact is 2 616 100 kg CO e for the mass timber building, and 3 485 064 kg CO e for concrete.
2 2
And the total mass of the CLT and glulam used in the mass timber structure is reported as 750 367 kg and
217 333 kg, respectively. No other wood-based materials are reported in the analysis.
If assuming 15 % moisture content in the mass timber products, the biogenic carbon is calculated as below.
For the mass timber building:
mm+
() 750367+217333
44 44 ()
CLT glulam
w = × 0,5 × = × 0,5 ×
Bw,
12 ()1+ω % 12 ()11+ 5%
= 1 542 710 kg CO e
For the concrete building: w =0
Ba, p
Then the displacement factor for this case is:
mm−
Ea,,pE w 3485064−2616100
f = = =0,5633
Ds, pec
ww− 1542710−0
Bw,,Bap
The results are summarized in Table 5.
[32]
Table 5 — Calculated displacement factor for building structure using mass timber based on
w m , m , Calculated f
Mass timber struc-
B,w E w E ap D
Concrete structure
ture
kg CO e/FU kg CO e/FU kg CO e/FU t CO e/t CO e
2 2 2 2 2
12-story residen-
12-story residential
tial building with
1 542 710 2 616 100 building with gross floor 3 485 064 0,563
gross floor area of
area of 12 900 m
12 900m
5.5 Literature review
NOTE The references sometimes use harvested wood products/HWP whereas this document uses wood-based
products. In this clause, the terms used in the original source have been used.
This clause summarizes several published literature reviews of displacement factors for wood-based
products and building systems. In addition, an extended literature search was made in preparing this
document.
It is common to observe that displacement factors vary considerably between studies, even for very similar
products and their functional alternatives. Some studies have calculated average displacement factors
[49]
across national systems. Soimakallio et al. used an average displacement factor for the whole national
activity of Finland, with a value of 1,2 t CO e/t CO e based on a range from 0,7 to 1,7 t CO e/t CO e for
2 2 2 2
different product types. They commented that this was higher than the value used in other national level
[50] [52]
studies, such as 0,4–0,8 t CO e/t CO e for Finland, 0,5 t CO e/t CO e for Switzerland, 0,6 t CO e/t CO e
2 2 2 2 2 2
[38] [47]
for Sweden and 0,5 t CO e/t CO e for Canada .
2 2
The review by Leskinen et al. (2018) on more recent studies and meta-analysis suggested an overall
displacement factor of 1,2 for wood-based products, see Table 6. The average displacement factor for
structural construction was 1,3, and the average displacement factor for non-structural construction was 1,6.
Table 6 — Average displacement factors (substitution effects) for wood-based product categories
[36]
(from )
Product categories Average substitution effects kg C / kg C wood-based
product
Structural construction 1,3
(e.g. building, internal or external wall, wood frame,
beam)
Non-structural construction 1,6
(e.g. window, door, ceiling and floor cover, cladding, civil
engineering)
Textiles 2,8
Other product categories 1,0 to 1,5
(e.g. chemicals, furniture, packaging)
Average across all product categories 1,2
[44]
Sathre & O’Connor reviewed 21 publications and summarized the displacement factors in the construction
field. They found a wide range of displacement values across different wood-based products that displace
alternative building products. The displacement factors ranged from a low of -2,3 to a high of 15, with most
lying in the range of 1,0 to 3,0.
[54]
A recently published paper by Taylor et al. provided displacement factors for various harvested wood-
based products to displace alternatives, see Table 7.

[54]
Table 7 — Displacement factors for wood-based product categories (from )
Wood-based product Alternative product Displacement factor (t CO e avoid-
ed / t CO e in HWP used)
Primary construction Steel 0,96
Sawn wood, plywood and veneer,
OSB, particle board, MDF
Floor Ceramic tile, vinyl sheet 0,99
Laminate, MDF
Floor Ceramic tile, vinyl sheet 1,59
Solid wood
Treated posts, poles and pilings Steel, concrete, fiberglass 1,4
Softwood or hardwood
Decking and fencing Wood-plastic composite 2,39
Solid wood
Pallets Plastic 0,34
Sawn wood, plywood and veneer, OSB
Furniture Steel shelving 0,36
Sawn wood, plywood and veneer,
OSB, particleboard, MDF, hardboard
Packaging paper Plastic 1,12
Mechanical or chemical pulp
Heating or electrical power Fossil fuel mix 0,68
Energy wood, pellets
USDA Forest Service recently published a national guideline for forest landowners as a reference to quantify
[40]
the greenhouse gas emissions and carbon sequestration at the entity-scale for agriculture and forestry. In
Chapter 5 of that document (the harvested wood products section), the displacement factors are presented
for the typical HWP categories and wood to energy substitution, see Tables 8 and 9 extracted below from
[40]
the guideline .
Table 8 — Displacement factors for material substitution: HWPs against non-wood-based products
(from Reference [40])
HWP Functionally equivalent Displacement factor (t Reference
non-wood-based product CO e avoided / t CO e in
2 2
HWP used
Softwood lumber One steel stud 0,99 Adapted from Reference [6]
Hardwood lumber One steel door 2,29 Adapted from Reference [6]
Plywood Structural construction 1,3 [36]
materials
Oriented strandboard Structural construction 1,3 [36]
materials
Other industrial products Non-structural construction 1,6 [36]
materials
Other industrial products Non-construction use 1,2 [36]

Table 9 — Displacement factors for energy substitution: woody biomass against non-wood-based
fossil energy and heating sources (from Reference [40])
HWP Displacement factor (t CO e avoided / t CO e in HWP
2 2
used)
a
Electricity
c
Mill residues 0,270
c
Logging residues 0,267
c
Softwood pulp 0,261
b
Heat (wood-based fuel)
d
Coal 0,68
d
Oil 0,57
d
Natural gas 0,45
a
Emissions for grid-based electricity were taken from Reference [5] using the national average profile.
b [34]
The calorific value of wood chips at 30 percent moisture content (12,2 MJ/kg) was used .
c
Displacement factors when the woody biomass generated electricity to displace the US grid-based electricity (mix of fossil
and renewable sources).
d
Displacement factors when wood-based fuel generated heat to displace the fossil fuel (coal, oil or natural gas) generated heat.
6 Examples of tier 1 displacement factors for selected products and product
categories
Based on the previous clauses and an extended literature review (list of references in the Bibliography,
including References [56] to [163] see also extracts from literature reviews referred to in 5.5), generic
displacement factors were defined. These examples of displacement factors for broad product categories are
listed in the table below.
Note that these examples are general indications that can be suitable for tier 1 applications, but deeper
analysis of an organization’s or entity’s delivery of products to the market can lead to different results. In
ISO 13391-3:2025, Table A.1 gives indicative displacement factors that can be used for a tier 1 approach.
If the organization chooses to report a displacement factor from this clause or from the literature in
addition to calculated greenhouse gas emissions from the wood-based value chain, extra considerations and
limitations can be described to avoid double-counting, since displacement factors from external sources
can include or exclude the wood-based product value chain emissions. At minimum, ISO 13391-1:2025, 6.3.3
requires that a statement be included with a reported displacement factor, explaining some of its limitations.
Most of the literature refers to displacement factors that include the wood-based value chain emissions.
Reporting these emissions separately can lead to double-counting.
Displacement factors can be lower or higher if the wood-based value chain leads to different levels of
greenhouse gas emissions compared with examples in the literature.
A deeper analysis can also lead to a more detailed set of product categories, which can in turn lead to higher
or lower calculated displacement factors. For example, a certain portion of packaging solutions can replace
glass or metal packaging, which would affect the displacement factor. Similarly, sawn wood products can be
destined to specific applications that can justify a different
...