which screws to use on the 22mm chipboard

[caretaker]

Hi All,
First of all, i hope everyone had a good chritmas, pity about the weather.

I need to ask a question, as i am not sure whihc size screw to use, as i need to screw the Chipboard tongue and groove boards on to the 8x2 joist. Can i use nos 8 x 2 or do i need to use nos 8 x 2 1/2", as i was thinking of using the posi head.

I will apply PVA glue on the tongue and groove and also on the joist, so there is very likely any chance of a movement.

I have lot of access peices whihc the tongue has been cut off due to servces were installed, example plumbing and electrical. Do you have any ideas how to make this solid fix, as after time they tend to squeak after people walking on it and it starts squeaking after a year or may be months depending on how many people walk.


Much appreciated for the advice.


Merry christmas and New year.

[speed]

you need the 2.1/2's manafacure recomend 4 fixings in the 600 width,

for the traps, dont make them tight, 2 boards rub together= squeak , leave a few mm gap,
also they need a 10mm gap round the perimiter for expansion, if they are tight they can also cause squeaks

[caretaker]

Boards are 2400mm x 600mm and the joist are spaced at 400 centre.

[speed]

if you havent got the boards already 18mm is plenty for 400c. save a few quid,

[caretaker]

Hi Speed,
Can i mix and match, as i have some screws left from other job, as i have half a box left of 10x2", Full box 10x 21/2" and full box 10 x 21/2" steel screws and the rest 8 x 21/2".

If i use 10's size screwhead is it ok to have 3 screws along the 600 width.

One more question is do i need to screw on every joist, as my board are 2400mm x 600mm, so approximatley 6 joist on 1 board, do i need screw on these 6 joist x 4 or is there a distance apart for the next screw to start.

Thanks.

[Steve61]

Hi Speed,
Can i mix and match, as i have some screws left from other job, as i have half a box left of 10x2", Full box 10x 21/2" and full box 10 x 21/2" steel screws and the rest 8 x 21/2".

I don't see a problem with that.

If i use 10's size screwhead is it ok to have 3 screws along the 600 width.

This would be fine if you were to apply glue to the joists IMHO, but at the same time pointless because the money saved on screws would be spent on glue/silicone.

One more question is do i need to screw on every joist, as my board are 2400mm x 600mm, so approximatley 6 joist on 1 board, do i need screw on these 6 joist x 4 or is there a distance apart for the next screw to start.

Unless you want to risk a squeeky floor then you must fix the flooring to every joist.

There is a specialised adhesive you can get, applied by mastic gun to the joists before laying each board, which I have fixed many floors with using ringshank nails. Never had a problem to date with this method. Any access traps are obviously fixed with screws (spax 60x5), excellent screws. Leave a good 10 or 12mm around the perimeter of the floor, also don't make the traps too tight (slight gap).

Hope this helps,
Steve

[speed]

as said should be ok with 3 fixings but id screw every joist. a box of 2 1/2 8s cost less than £2.50

for the spacings if you are using 3 id go 1" from each edge and one in the centre, you need premiter fixings as it will clamp the t&g together

[caretaker]

Hi Steve
What does IMHO means ?

When you say perimeter fixing, does it mean you are fixing 3 screws on the wholwboard 2400mm length, as you mentioned above 1" from each edge and one in the centre.

[speed]

IMHO = in my honest oppinion, i think

no, it needs 3 fixings on each joist 1" form each edge and one in the centre is across the 600mm way so you have 21 fixings in each board

[Steve61]

IMHO = in my honest oppinion, i think

no, it needs 3 fixings on each joist 1" form each edge and one in the centre is across the 600mm way so you have 21 fixings in each board

Hi there,

Correct: IMHO = in my honest opinion & yes to the above.

You absolutely must screw/nail/fix (whatever) into each and every joist.

Steve

[jg]

I always thought it was In My Humble Opinion, but that's not really important :)