Gazebo - Timber Type

lunches123

Hello all.

Good morning.

Can I ask, please, for your advice on the following issue I encountered over the last week:

We recently bought a Gazebo. It was specified by the vendor as being made from Larch wood.

However, when it was delivered, it was labelled by the manufacturer as 'Douglas Fir'. I queried this with the vendor, and after initially telling me it was a paperwork error, later, they confirmed it was actually a different wood.

So - Im hoping someone here might be able to advise me on what to do next - should I return this to the vendor, who has offered me a refund, OR, should I keep it?

Would Douglas Fir be hard wearing, and as good as Larch (as the vendor claims), or is it an inferior wood?

Would I need to treat the Douglas Fir wood? Would it last as long? Is it weaker? etc

A lot of work has gone into preparing the ground (levelling, concrete foundation etc) and its disappointing to be in the situation now where we can't finish it.

Appreciate your guidance on what to do.

Thanks.

10-10-20

I was temped to dismissively say that any fir is going to be quick-grown, light rubbish, but it seems that it's not always true and that it's in some ways comparable to larch. There is a good breakdown here and it suggests that larch is more rot-resistant, but more difficult to work with, and the fir typically cheaper.

https://logietimber.co.uk/docs/douglas-fir-vs-larch/

So on the basis of the product not being as described they have offered you a refund… but you're going to have to decide whether you want to go to the extra effort of protecting the fir for the Irish climate or not.

Oh - and I also looked up the density of both larch and Douglas fir and they are both similar in and around 530kg/m3, so that also tells you that they have similar characteristics in terms of weight and aren't a massive contrast in terms of being a cheaper shipping option.

Lumen

Larch is definitely more durable than Douglas Fir, particularly Siberian larch (because the grain is tighter than native larch). Douglas Fir needs to be treated in an exposed application, whereas Siberian Larch does not.

The advantage of Douglas Fir is that it's available in longer lengths and larger dimensions so good for big, long beams.

All that said, neither should be in ground contact, and provided that you treat the Douglas Fir appropriately it should last as long as you could reasonably want. If it's a gazebo it should have a roof, so it's not going to have horizontal surfaces directly exposed to rain like (say) a pergola would. As long as the roof is done right, the timber is not in direct ground contact and there's appropriate guttering and downpipes in place (so as to avoid lots of rain splash) and the wood is decently treated then I wouldn't worry about it, enjoy your gazebo.

edit: this chart possibly adds more confusion than it removes

lunches123

Thanks to you both for your replies above. I appreciate your guidance. Perhaps Douglas Fir may not be as bad an option as i first thought.
thanks again!!!

The Continental Op

My post from the DIY thread

Stopping top of fence posts rotting with flashing tape

"Best wood preservative I've used and I use a lot on chicken runs and sheds is Protim 265 but they don't seem to be making it anymore. As a result I've been using this

https://justfunplaytowers.ie/product/3-in-1-wood-preserver-dark-brown/

 there is also a green and a clear version

which is very similar and seems just as good - smells like it should kill everything and soaks in well - unlike the low odor water based preservatives which imo are rubbish."

Use the clear and give all the joints a good coat when assembling then soak all end grain and if you can two coats all over.