Plywood and Formaldehyde

[MortarThePoint]

Some will already know, but a quirk of my build is I am trying to avoid introducing anything that will off gas lots of formaldehyde (or other things too). I'm less concerned about off gassing paint which lots of people worry about. The reason for that is that the layer is very thin and we aren't living in the house yet, so it should hopefully have finished by time we are in. That's not to say that it's not a point of discussion with 'the client' on occasion though.

 

I have spent a lot of time looking at Plywood and thought I would dump some of my learnings here for anyone who may be interested. There may be inaccuracies, so feel free to correct.

 

Glue: Remember that the wood itself contains formaldehyde, so the main variable is the glue. The two most commonly used glues are Urea Formaldehyde (UF) and Phenol Formaldehyde (PF). PF is stronger and emits less, but is more expensive.

 

Europe (& UK): This is according to the standard EN 13986, the lower class of which is E1 (0.124mg/m3) which has higher emissions than many other standards. There is an informal E0 classification (?? mg/m3) and Germany have adopted an E0.5 or E05 limit (0.08mg/m3). Ikea have apparently used an E0.5 type standard for a while. It's all about to change with the adoption of a new standard, EU 2023/1464 which introduces a tighter limit (0.062mg/m3 for "furniture and wood-based articles"). That new standard will be effective from Aug 2026, but some companies are already stating compliance. It's worth noting that Finland also have their own standard, M1, with a limit of 0.010mg/m3, so 12.4 times tighter than E1.

 

USA: California has the CARB Phase 2 (CARB P2 or CARB2) limit of 0.05ppm for hardwood plywood. I'm not sure how they work it out, but I've seen articles that say Europe's E1 is equivalent to 0.10ppm so is twice CARB2. CARB2 is adopted nationwide, but the office standard is EPA TSCA Title VI limit which is the same 0.05ppm limit.

 

Japan: They have a 4-star scale, the strictest of which is F**** (or F4) with a limit of 0.005mg/m2h. Despite using a different measure from the rest, I believe this to be the strictest standard.

 

China: As per Europe's EN 13986, but adding E0 (limit 0.050mg/m3) and ENF (limit 0.025mg/m3).

 

Effectively being in Europe means we are currently only governed by EN 13986 and so most products only state that they are E1 and, quite reasonably, that's all most suppliers understand. There is a chance of finding M1 compliance stated which is one of the tightest limits globally. Some manufacturer's (e.g. Riga) clearly set out the various standards that they meet in a more global context. For example here is an extract from Riga birch ply:

Some example products I have found:

• Birch: Riga Ply (meets F4), Wisa may be good but documentation not so clear
• Radiata Pine: AraucoPly (meets F4)
• Poplar: Panguaneta (meets F4)
• Marine: I have yet to find a marine ply (i.e. meeting BS 1088) which meets any formaldehyde class other than EN 13986 E1. I would like to though so if anyone has found one please add it here

 

Other notes:

• NAF - no added formaldehyde which means only that which comes from the wood.
• OSB3 easily available as NAF (e.g. SterlingOSB Zero OSB3 widely carried by merchants)
• Glass wool insulation - Knauf' standard "Ecose Technology" uses a formaldehyde free blowing agent
• MDF - Medite Clear is an NAF MDF, but no moisture resistant version as far as I know
• The other chemical often considered is pentachlorophenol (PCP)

[Alan Ambrose]

Thanks for that, v interesting.

[ADLIan]

Knauf ecose is a binder not a blowing agent. It states ‘no added formaldehyde’ - does this mean totally formaldehyde free??

[MortarThePoint]

24 minutes ago, ADLIan said:

Knauf ecose is a binder not a blowing agent. It states ‘no added formaldehyde’ - does this mean totally formaldehyde free??

 

Binder is correct, thanks. This link says "Products using ECOSE Technology are formaldehyde-free."

[ADLIan]

Link is to America. Check UK site

[Alan Ambrose]

>>> It states ‘no added formaldehyde’ - does this mean totally formaldehyde free??

 

Maybe in the sense that smoothie makers say ‘no added sugar’ but the product contains plenty of fruit-based sugars.

[SteamyTea]

Is it, at the levels we see, a real problem.

https://www.gov.uk/government/publications/formaldehyde-properties-incident-management-and-toxicology/formaldehyde-toxicological-overview

[MortarThePoint]

The French have their own classification system that covers building products in general: ÉMISSIONS DANS LÁIR INTÉRIEUR

Their strictest classification is A+ which has a Formaldehyde limit of 10ug/m3. NB: That is the same limit as the Finnish M1 classification.

 

That has led me to a manufacturer of Marine Plywood (BS1088) that is A+: Joubert Plywood

No idea if you can get it anywhere in the UK, but if it was a big project that needed the answer there it is. Irritatingly, there English language page and datasheet don't have the A+ rating shown, which again shows how hard it is to find the information for this topic.

Edited October 22 by MortarThePoint