Boarding loft space

[wombats]

I know there are loads of posts on this subject as i have read pages and pages.

I am wanting to board my loft and i think i am right in saying that i will need 18mm chipboard. Now can i just buy 8' x 4' boards and then just cut them to size or would they need to be routed so that they overlap? Also there is a lot of mention about putting down battons to raise above wires, is it neccesary to lay these the opposite way of the joists or can they just be put directly on the joist and just leave a gap where the wires are?

Does there need to be a gap between the rockwool insulation and the chipboard?

 

[wombats]

Can't anybody give me a little help on this?

 

[JohnD]

the reason you have no replies is, as you say "there are loads of posts on this subject" and all the answers have already been given.


If the cross-timbers are laid across the old timbers they will help spread the load and keep the floor more rigid when all screwed together. If you do that you can space them so that you do not have to cut the chipboard.

You should have a space to allow air circulation to avoid condensation.

I'll wager £5 that you will not be able to get 8x4 boards through your loft hatch.

You will quite likely be able to get 8x2 boards up there.

Ply is stronger than chipboard, and WBP ply will not fall apart if it gets wet (like chipboard will).

 

[wombats]

I have read loads of posts and didn't quite find the answers that is why i posted.

If you do that you can space them so that you do not have to cut the chipboard.

Nice tip.

You should have a space to allow air circulation to avoid condensation

I only intend doing 2/3rds of the space anyway.

I'll wager £5 that you will not be able to get 8x4 boards through your loft hatch.

I mentioned in my post about buying this size and then cutting them down to save money.

I intend buying my screws from Screwfix as i am placing an order anyway.Could you tell me which screws i should use?

 

[Hysteresis]

B&Q do a proper loft board pack made from 4' X 2' - 18mm chip board. These packs are tounge and grooved and I might add this is very advisable. If you dont use T&G your joins obviously will move apart under load.
Yes Ply is better but substantially more expensive.

 

[wombats]

Thanks for the tip with the tounge an groove thing. I don#t intend to have heavy loads in the loft it will just be boxes and the odd small electrical item just used for storage. I thought that it may be cheaper to buy 8x4 and then rip it down to the right sizes and then use a router on the edge to make tounge and groove as i have the tools to do this.

 

[Hysteresis]

Hi Wombat,
Although you only intend storing the odd box, the greatest point load you will have is yourself walking on it and in my experience that is where you get the problem. Not only do the joins move, but because the individual boards ar only 2' wide, when they move they also tend to break or crack, with the obvious consequences. T&G totallilliminaytes this problem as the floor becomes an integral unit.
My experience of routing Chipbourd is not good. The stuff tends to break up a bit and weakens the join. You may find it false economy not to say a lot of extra work.
Good Luck

 

[Hysteresis]

That rediculous word in my mail should have read totally eliminates, finger trouble - sorry

 

[wombats]

I understand what you are saying about the joinys and movement. Also i can see what you are talking about with chipbaord flaking. Looks like i will just have to go for the narrowest boards then as my loft hatch will not take the 2 foot wide ones. Now i need to know which screws to use.

ps i did work out what totallilliminaytes was

 

[Hysteresis]

The screws are not really load bearing and are only there to effectivly stop the boards moving and to hold them down, so I would use something like
1.5" or 1.75" , 8's countersunk posidrive Twin thread, Screwfix item numbers 17605 or 19568. As Screwfix charge postage you may be better off at B&Q who I believe are the same company as Screwfix.
When laying out your boards, wherever you can try and get the joins on a joist. Obviously you can't achieve this at every join but the more support you can give to the joins the better.

 

[wombats]

Thanks for those codes i will take a look, i am ordering some things from screwfix anyway so i can just add these to the order.

When laying out your boards, wherever you can try and get the joins on a joist

Are you refferring to the joist or the cross-timbers mentioned by JohnD?

 

[Hysteresis]

I think JohnD is referring to laying cross timbers across the roof truss joists first. This may be the correct way to do it but I, and I think most other DIYer's, drop the loft chip boards straight on to the roof truss joists and screw 'em down.
Maybe JohnD is referring to the type of construction you would do if you were doing a proper Loft conversion. I would get an experienced loft converter in for that sort of job, but just for storage, I think straight on to the roof truss joists is all that is required.
I certainly would appreciate some advice from a professional if my approach is wrong and against building regulations.

 

[Deluks]

I think JohnD is referring to laying cross timbers across the roof truss joists first. This may be the correct way to do it but I, and I think most other DIYer's, drop the loft chip boards straight on to the roof truss joists and screw 'em down.
Maybe JohnD is referring to the type of construction you would do if you were doing a proper Loft conversion. I would get an experienced loft converter in for that sort of job, but just for storage, I think straight on to the roof truss joists is all that is required.
I certainly would appreciate some advice from a professional if my approach is wrong and against building regulations.

No John is referring to a better way of boarding a loft for storage. This method will certainly not meet any building regs. Counterbattening across the joists will spread the load and make for a loft floor that will carry more weight, as the load will be spread more evenly. This will prevent any sag in the joists and more importantly prevent the bedroom ceiling plaster from cracking under the strain. It also means you can have a couple of extra inches insulation plus you can avoid cables and pipes.

True that most people just plonk the chipboard on to the loft timbers but counterbatten is just a better way to do it. Doesn't take long and for the price of a few lengths of 2x2 and box of screws is well worth it.

 

[Hysteresis]

Thanks Deluks. Armed with your advice, your way is certainly the way I will do it in future. I am about to re-do my loft within a couple of months and I will undoubtably take your advice.
Thanks again

 

[wombats]

The advice you both just gave there is very appreciated. So i am looking to cross batton the joists with 2x2 or should it be 3x1 as i have seen mentioned a few times before? Also in my loft i have the insulation between the joists and just over a year ago i had an insulation company add more to it to bring it up to the required amount,but they layed it the opposite way. Will i have to re-lay this the same way so i can see the joists the fasten to?