a warning re wet timber.

[saveasteading]

We had a delivery of sopping wet timber and sent it back.

 

From asking around it seems that all suppliers round here keep tanalised (and other treatments) timber in the yard, uncovered. They think that is ok because it won't rot, and they regard it as 'outdoors' timber. Few have enough shelter, and seem to me to have far too much stock, perhaps as an investment.

Their own trade specifies that all wood should be protected and ventilated. But they don't much care as long as it is selling. They don't invest in tarpaulins.

 

The brochures may say kiln dried, but then forget to mention ' and then left outdoors in the rain until somebody accepts it.'

 

The thing is, that we are using treated timber for the shell and are investing in the long term with no worries about dampness , woodworm  etc. I know from experience that wasps can find their way into tiny gaps and like to chew wood for their nests, Treated wood won't be chewed twice. Plus as we are building in the open, it was bound to get a bit wet for a while.

 

 

An earlier delivery was also wet, and it bent by up to 50mm over a 6m length, making it unsuitable for structure.  Half of these were also sent back, without argument.

 

So the moral is to tell your supplier that the timber must be dry in accordance with their industry guidelines. They might  decline, but they can also set some aside under cover, or buy it in new from the docks.

 

This probably does not apply to CLS which presumably is regarded as internal timber.  We are ordering some so will see.

 

Structural timber must be dry so that it keeps shape, especially in the vertical. 

And I dread to think what happens to a floor when the joists twist. Do the floor screws reach?

Plus you don't want it twisting after construction.

The timber industry body agrees, except that the merchants dont seem to know that.

 

 

 

[SimonD]

6 minutes ago, saveasteading said:

The timber industry body agrees, except that the merchants dont seem to know that.

 

There are a lot of people I know who are fed up with my moaning about this. I went to a merchant not long ago that a lot of builders around here use and swear by for timber quality. I then looked at their yard only to see the treated timber stacked in a hardcore yard that  and not even paved and then the timber completely open to the elements. Needless to say I did not buy my timber from there. The issue is also protection from sunshine because as soon as the sun falls on some exposed damp timber, let the warping begin.

 

The problem is that it's almost impossible to find a merchant that properly follows the standards. Even when stored under cover, the warehouses are almost never humidity controlled either. I use one supplier who has a closed humidity controlled warehouse you're not even allowed to access but have to wait outside for the forklift to bring your order, but even they store a lot of treated timber outside (with a little cover).

[MikeGrahamT21]

Places like B&Q and Wickes are actually quite good places to buy timber from, since their warehouses are also shops, they are heated to some extent and ventilated, but even there some of it can be warped, or just not dried enough as the tanalising happens after kiln drying (iirc), and often isn't left long enough to dry before being shipped to store

[saveasteading]

We have gone with 'the devil you know' as they have agreed to buy in what we need and keep it indoors. obv this is no risk just cash-flow and a bit of space, but shows willing.

We do have to do an urgent tally of expected quantities.  (we have several km of timber going in)

I can't understand why they can't put tarpaulins over. That is a one-time cost. The industry could make them to exactly suit bundles of timber at a low cost. 

 

Their industry document shows this. I guess the merchants just throw these covers away because the yardmen can't be bothered.

 

I'm quite cross about this and worry somewhat about the quality of  other buldings... eg the ones where our rejected timber goes to later. Also that the majority of project managers must be accepting this stuff.... and what else do they not care about?

 

 

 

 

 

In case anybody wants more info.  It quite clearly says that keeping it dry is very important.

 

 

https://timberdevelopment.uk/are-you-keeping-your-timber-stocks-safe/

 

And the following summary comes from AI so is hardly hidden info.   The yellow is my highlighting.

 

Based on TRADA guidelines, proper storage of timber on site is critical to prevent moisture changes, warping, distortion, and staining. 

 

Key Principles for Timber Storage

• Keep Off the Ground: Store timber on dry, even ground to prevent moisture uptake, preferably on elevated, level bearers (e.g., 75mm x 75mm).
• Protect from Elements: Use waterproof, breathable covers to protect from rain and direct sunlight, which causes warping.
• Allow Air Circulation: Ensure air can circulate around the timber, even under covers, to prevent condensation and moisture buildup.
• Avoid Contamination: Keep timber away from standing water, muddy areas, and sources of damage. 

[Alan Ambrose]

Yeah it’s a bit nonsense, but we’re finding the better quality timber doesn’t warp even if it’s wet.

[saveasteading]

4 hours ago, Alan Ambrose said:

the better quality timber doesn’t warp even if it’s wet.

Agreed.

Of 80 lengths of 6 x 2, we took wet in an earlier batch, we sent back 40. 

I had wrongly assumed that the vacuum treatment would have collapsed and filled open pores with the treatment chemical. BUT someone suggests that was the case with old, oil-based treatment but no longer.

 

The 40 rejected were up to 50mm bend over 6m. They will sell them to less critical builders. Cutting into 3m will make most passable.

 

I once needed some 2 x 2 in a hurry so accepted the dregs from a merchant. One had a complete 90° twist over 4.8m.

[Mattg4321]

It is a nightmare especially at this time of year.

 

Doesn't really help when you need large quantities, but that's the beauty of Wickes etc. You can stand there for as long as you like rooting through timber to find something straight and true. 

[ProDave]

9 minutes ago, Mattg4321 said:

but that's the beauty of Wickes etc. You can stand there for as long as you like rooting through timber to find something straight and true. 

And then within a few hours of you getting it home and into your house, it becomes the shape of a banana.

 

 

[Beau]

 

In my experience, kiln-dried constructional timber is not dried to the same extent as hardwoods. I’m a furniture maker, log seller, and miller by trade, and when buying in hardwoods for furniture they are dried to around 8–10%, which is close to what they will sit at in an average home. When I’ve tested construction softwoods, they’re normally in the 16–20% range, so they will shrink and warp more if used inside the heated envelope, but are fine for external use as is.

Worth noting that even though it’s a pain buying in timber that’s been soaked by the rain, it will quickly dry back to its kiln-dried moisture content, as this water is not bound in the cells of the wood. Getting it from 16–20% down to 8–10% for the home can be a slow process, but softwoods dry more quickly than hardwoods. As mentioned, the wood in the DIY sheds is often much drier due to its storage environment, but also much more warped and twisted, as it’s dried beyond what you get at the builders’ merchants.