Loft boarding project started

Having a bit of an annoyance with these OSB loft boards.

First I bought 6 packs from Wickes which were all fine. Then I went back for 6 more packs and of these, 4 packs had a slightly different cut on the T&G profile meaning they didn't sit flush with the original ones. Returned to the store and all new packs for sale have the slightly modified profile so didn't fit properly.

Went to B&Q with my offcuts sample, and their packs (same manufacturer, same packaging), all seemed to fit perfectly so I bought 6 more packs.

However on fitting, 2 of these packs also have a slight variation in T&G profile so not sitting perfectly flush.

Have to go back again today now and see if I can get the packs which match the original ones.


Update - of the packs at B&Q, found 6 more packs that had the right profile, the rest weren't. There's nothing on the packaging (except for one thing, spotted later, will come on to) that indicates a different batch. Barcode is identical, no ID or date marks. Anyway, dug around and moved a load of board packs to get to some at the back - and lo and behold - a whole pallet full of the ones I need.

So clearly there has been something changed at the manufacturer that is meaning a slightly different cut on the T&G. I am not sure whether I have the old version, or the new, but clearly something is different.

Now, what we then spotted was the printed label on the front of the packaging shows an image of a completed loft using these boards. On the one type of pack, the image is a greeny tint, and on the other types of packs, its more of a yellowy tint. Its otherwise exactly the same layout, and image.


Edit - here's the packaging. Spot the difference. Even if I spotted this in store I would assume just printing variation.

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Either the tooling wore out or they changed who was manufacturing it I suspect.
Printing probably indicative of a different print run or a different printer as well.
Yeah I agree but very annoying having to transport opened packs back to Wickes/B&Q on two occasions, trying to explain it at the refund desk, and then trying to hunt through the boxes looking for the right ones.

Now we know what to look for, its obvious, but there was no warning in advance that these could have been different. There's colour variation in the boards as well which we've just noticed, but you can only see it putting new and old side by side.

I can understand variation in packaging and colour of course, but to have a different T&G profile is pretty poor especially when there's nothing on the packs to indicate otherwise and they are all mixed up in the shop.

The variation was only enough to cause 1mm or so difference in flushness but even so, when you start dragging/sliding things across the bare floor it will start to splinter at that point and OSB is terrible for that anyway.

Its solved now so all good in the end.
 
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Either the tooling wore out or they changed who was manufacturing it I suspect.
Printing probably indicative of a different print run or a different printer as well.
Was thinking exactly the same, or as was the case for some moldings I had, the manufacturer had a number of factories churning out the same product and the serial number had one digit different which indicated the factory they came from.
 
Maybe use bitumen paint to stick a piece of canvas over the tear the cover in the paint as well.
I was thinking of it but if it doesn't work its going to make a right mess. Does bitumen paint/mastic dry/harden?

There's also the flashband primer I could try.

A few things I could try but have to buy a new product every time of which I'll only use a tiny bit, and if it doesn't work its wasted.
 
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a bit of butyl tape could work
The problem I have with all these tape solutions is that I can't apply hardly any pressure to the area, as there's nothing behind the ripped area to press against.

Considering some bitumen substance with a reinforcing mesh scrim tape of some sort, and trying to layer it up.
 
Your problem is the surface of the felt, its a rough surface so little for stuff to grab hence why I said bitumen based primer of some sort then flashband.

Most people don't bother though, felt gets old and crap and starts to pretty much fail under its own weight. Means you get more dust in.
If water is consistently getting to the felt then you have a roofing issue anyway and thats going to rot the roof battens over time.
 
Your problem is the surface of the felt, its a rough surface so little for stuff to grab hence why I said bitumen based primer of some sort then flashband.

Most people don't bother though, felt gets old and crap and starts to pretty much fail under its own weight. Means you get more dust in.
If water is consistently getting to the felt then you have a roofing issue anyway and thats going to rot the roof battens over time.
Water isn't the issue its the insect prevention. Both major tears in the felt are the areas where I found the wasp/insulation combo nests.
 
Here is the biggest tear in the felt. You can see how the Gorilla tape has just peeled straight off.

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Which tape is that? Doesn't look like the stuff I used to join/patch my DPM - that stuff is all black. Yours looks white, is it more like a gaffa tape?

Not that I think it'll make much difference, still have the issue of no backing to press against.
 
Which tape is that? Doesn't look like the stuff I used to join/patch my DPM - that stuff is all black. Yours looks white, is it more like a gaffa tape?

Not that I think it'll make much difference, still have the issue of no backing to press against.
That one is the Gorilla waterproof patch and seal tape. Very sticky, self amalgamates on anything but felt it seems.
 
Project finished except for a bit more insulation and the roof felt patch up.

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I'm pleased with it. Floor feels rock solid.

Total cost was about half a 5090.

About 20m2 so just under £50 per square meter all in.

What surprised me in terms of cost was the hardware (mostly joist hangers and screws).

Timber: £250
Floor panels OSB: 18 packs of 3 total: £270
Hardware: £340
Electrical: £48
Insulation £100
 
I had a similar felt issue on a 30+ year old house. It was actually a better fix to get onto the roof, carefully remove the roof tiles where the tear was, and then replace from that side. Felt was fixed to the battens with nails.
 
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