treated vs untreated timber

[cuffster]

hi

I'm going to build a timber framed extension (1st floor) and am not sure whether to use treated or untreated timber. Obviously untreated is cheaper but is this false economy?

Many thanks for any replies

 

[^woody^]

The cost of treated over untreated is pennies. However, you will probably use CLS timber which will be supplied untreated.

In some parts of the country susceptible to wood boring insect attack, treated timber will be mandatory.

But it is not specifically a requirement to use treated timber

This is copied from a TRADA guide

"BS 5268-5 Code of practice for the preservative treatment of structural timber includes external wall framing in risk category 2C (where the risk of fungal decay is low but where remedial work would be difficult and expensive). Treatment is considered optional or desirable and so the timber would commonly be treated."

Speak with the local BC office to see if there is any local requirement.

 

[cuffster]

thanks woody.

i was going to use untreated but a mate who's a chippy said he only ever used treated. As the wood wouldn't ever be exposed to the elements I couldn't see why it would matter. Going by the extract it would seem prudent to use treated for the timber frame and joists and untreated for the internal stud work.

 

[Deluks]

For the CLS, Just get a 5 ltr can of cuprinol 5* and give them the once over when they are delivered.

 

[JohnD]

any house can get a long-term minor water leak.

 

[Deluks]

any house can get a long-term minor water leak.

Good point John, my friend purchased a house couple of years back, the kitchen ceiling joists were rotten at one end due to water getting through some dodgy extension flashing and running down the wall. The polystyrene tiles did a good job of hiding any water evidence