Conservatory/Greenhouse hardwood choice

[paultr]

Could anyone give any advice which hardwood would be suitable for replacing parts of a conservatory which is attached to te side of the house?
The structure was rebuilt around 20 years ago out of softwood and the cills have now rotted and I need to replace them and also some of the glazing uprights.

I have spoken to a local woodyard and they stock Sapele and Maranti - are these too good? The guy said I could consider Hemlock but they do not stock that.

Anyone got any comments ?

 

[stevethejoiner]

For cills I would go for Iroko, it does not finish as well as Sapele and Maranti but it will last longer and its cheaper.
Unless you are replacing all the softwood and only doing some of the Jambs and Mullions (the uprights) why not use pressure treated softwood. Whatever you use put back now in pressure treated softwood will last longer than anything your not replacing and the paint will hold on softwood far better than hardwood.

 

[paultr]

Thanks Steve - when you say pressure treated do you mean it has some kind of preservative/anti rot/fungicide stuff in it?

If so, is it safe to machine and sand or do you have to wear breathing protection? - sorry to be so thick - I have never done much woodworking before but have heard about the risks with MDF although I think that is the resin in it.

 

[stevethejoiner]

Nothing major to be concerned about.
I would ask your local woodyard what treated timbers they have and what chemicals are used. There are a few types, the most common is TANALISED TANALITH and TANATONE. I believe they all have copper in them but the manufactures say only normal HSE is required when working on treated timbers as long as the chemical process has dried.
If worried, you could simply prepare your wood sections ready for fitting and brush or soak them in an off the shelf preservative, but still be HSE minded. Allow to dry before painting.

 

[AronSearle]

Pressure treatment carried out by most suppliers only goes several mm's deep, so If you start planing it you take away most of the treatment, cut end grain you should obviously re-treat.

Meranti is rated from slightly durable to durable, and so requires preservative treatment (many people argue this is wrong, durability testing shows otherwise).

Hemlock is not durable and will need treatment.

Sapele is moderately durable = no treatment needed.

If that's what you local wood yard has, go for sapele.