Plywood walls in new build

[Sara Wade]

Hi

I have seen amazing designs using birch ply wall panelling but cannot match with building regs. How can this be done? I think I need C S-2 D1 for ply wall in high circulation area (landings) and I don't know how I can get ply to comply? Any thoughts, being warned off by architects but I keep seeing pics everywhere so someone must know!

Thanks

[ProDave]

It will need a clear fireproof coating.  I have seen it done before. I even saw one house with OSB as the finished wall surface and that passed BR with a coating.

[JohnMo]

Because you see pics everywhere doesn't mean they comply with regs of the country you live in.  If architect is warning off there will be reasons.

[Russell griffiths]

It will cost a fortune to get right, but if that’s what you want. 

We are having a timber ceiling, it will be 3 times the cost of plasterboard and paint, but I like the look so it’s happening. 

Fireproof coating again. 

[JohnMo]

Amazing how fashions change.  20 years ago you pay to get rid of a wooden ceiling,. If fact I did.

[SteamyTea]

7 minutes ago, JohnMo said:

Amazing how fashions change

My house has the original cheap 1987 kitchen.  Then I had the place valued a few years back, the estate agent raved about the new kitchen.

I have left my artexed ceilings alone, one day, one day.

[Dudda]

Two options. Either get fire proof ply which they usually pressure pump fire protection chemicals into or you paint it with clear fire instrument paint.  Most people go the paint option. Either option will be more expensive than plasterboard.

 

In one project I worked on with exposed joists and sarking boards which needed to be fire rated the QS had a great cost saving idea. My drawings showed instrument paint but they suggested fire proof sarking boards as it was cheaper than painting. I agreed as visually they were similar. Problem was the fire engineer said the joists also needed to be protected. The whole roof couldn't now be sprayed with fir instrument paint as it would void the warranty of the sarking boards so each joists had to be hand painted. It worked out more expensive. Do you're research thoroughly first before starting or committing. 

[SteamyTea]

I wonder how the WikiHouseFoundation treat the ply.

 

https://www.vam.ac.uk/articles/building-a-plywood-house

 

https://www.wikihouse.cc/

 

 

[nod]

If it’s the effect that you like 

Plasterboard as normal 

Fire tape Tge joints and ply over the top 

[SimonD]

1 hour ago, Sara Wade said:

cannot match with building regs. How can this be done?

 

Our BCO has just asked for certificate of treatment using a product like Envirograf or Flametect (there are others). I will most probably be using Flametect https://www.fireproofspray.co.uk/

 

What you basically need to do is call the company selling the protection product, explain your plans and they will provide the right product and corresponding certificate for BC.

 

15 minutes ago, nod said:

If it’s the effect that you like 

Plasterboard as normal 

Fire tape Tge joints and ply over the top 

 

I'm not sure whether that will be ok? It was explained to us that the fire treatment is primarily to prevent flame spread which this may not do?

[Dudda]

19 minutes ago, nod said:

If it’s the effect that you like 

Plasterboard as normal 

Fire tape Tge joints and ply over the top 

Depends if you're trying to stop the spread of flames through the rooms which the plasterboard would fix or the surface spread of flames which it wouldn't. Generally this isn't accepted (again depending on use and location). 

[bob the builder 2]

HI All

 

I am considering some exposed glulam beams.

 

Will these also have to be clear coated with clear fireproof coating ?

 

Many thanks 

[Dudda]

4 minutes ago, bob the builder 2 said:

HI All

 

I am considering some exposed glulam beams.

 

Will these also have to be clear coated with clear fireproof coating ?

 

Many thanks 

If they're at large centers, eg 1200 or more, and you've plasterboard between them, then no as the fire won't jump between them and spread easily.

 

However if the glulam beams are holding up a floor above then it depends on the size of the beams as they have to support the upper floor level in a fire for a certain period of time if someone is stuck up there.  If the beams are oversized then it will take ages for them to burn and loose structural integrity then they could be fine and don't need clear fireproof instrument paint. Your engineer can tell you this.

[nod]

2 hours ago, Dudda said:

Depends if you're trying to stop the spread of flames through the rooms which the plasterboard would fix or the surface spread of flames which it wouldn't. Generally this isn't accepted (again depending on use and location). 

I don’t think there would be any building rules to stop you doing this It’s quite common to have mdf panels throughout 

Its more about stopping the spread of fire between floor 

Only 30 minutes on some of our jobs

[saveasteading]

The intumescent varnish is rather thick and can be noticeable. 

It is essential to do this properly, I have seen a fire test on a wooden faced wall and it is scary how quickly it flares up and smoke fills the room.