Loft hatch advice

DG · Post by DG » Sun Sep 28, 2008 7:19 pm

I am replacing a hatch in the loft which needs to be the same dimensions as the one I'm taking off and very sturdy as it will be walked on by my son and friends. Any advice on which type of board I should use will be appreciated as I can't seem to find any thick enough! The dimensions are 755mm x 1255mm x 40mm. Thank you.

chippymike · Post by **chippymike** » Sun Sep 28, 2008 7:29 pm

40mm thick loft hatch? why so thick and why it need to be shut to walk on?

DG · Post by DG » Sun Sep 28, 2008 7:35 pm

The loft is my son's pent house and it needs to be closed to shut the racket out and to give him privacy - it acts as a door at the top of the stairs (his own design!). There is half a hollow door in place at the moment but this really needs replacing with something sturdier. The 40mm is to fit in with the existing framework.

big-all · Post by **big-all** » Sun Sep 28, 2008 11:33 pm

the trouble you have is anyhing that size and solid will weigh a ton

you either need to use somthing like 22mm pine with a frame or make up a hollow structure with 2 skins of say 12mm on top 22mm frame and 6mm bottom skin

joiner_uk · Post by **joiner_uk** » Mon Sep 29, 2008 4:19 pm

You could use 18mm blockboard and glue the 2 pieces together with PVA to make 37mm thick. This will be very strong.

Shame about the size 1255 you could of used 1 8'x4' sheet (2400x1200) but you will need 2 sheets.

Which way will the door open?

My only concern is safety!

I would have the door open up/in then you can support the door better rarther than rely on a lock to hold the weight of the door + your son

Will be a very heavy door

DG · Post by DG » Sun Oct 12, 2008 4:47 pm

Sorry for the belated reply I was distracted by the million and one other things which need doing. Thank you for your suggestions I can see the merits in both ideas so will have to have a think - will 12mm be strong enough to walk on? The existing door opens upwards with a frame around the hatch which stops it from falling through. I'm only replacing the actual door itself as the rest is ok.

Thanks again.

joiner_uk · Post by **joiner_uk** » Sun Oct 12, 2008 6:26 pm

If you mean 12mm total thickness, no

Your average floor boards are 18mm thick and the joist spacing are usually 450 mm span. Your span is nearly double so double up the thickness

big-all · Post by **big-all** » Sun Oct 12, 2008 6:57 pm

18mm ply minimum even then its twice the recomended span for flooring at 400 centres

why not buy
1 sheet 12mm ply[8x4]
1 sheet 6mm ply[8x4]

3 lengths 18[20]x44mm 2.4m par timber

cut the 12mm to size cut 2 lengths timber to size of the short sides glue and screw into place flat

cut one 2.4m into 2x1165mm for the sides[measure the actual gaps] glue and screw into place

cut the remaining timber into 660mm lengths [5!!] space evenly along the frame

cut other ply panel to fit glue and screw into place

you now have a strong rather heavy door l o l 12mm surface up

is it not possible to make 2 doors part length say 627mm ot there abouts!!!

o well took me so long to compose this reply that uk beat me to it

DG · Post by DG » Mon Oct 13, 2008 4:18 pm

Thanks again - sounds like a good solution to my problem. I'll give it a go and get my son some weights so he open it.

Hoovie · Post by **Hoovie** » Mon Oct 13, 2008 4:33 pm

Assuming it is hinged one side, using a chain & pully with the right gearing conencted to the other, the effective weight can be significantly reduced - maybe even have a motor

Tryanything · Post by **Tryanything** » Mon Oct 13, 2008 8:14 pm

To be honest i'm not happy with the idea of the door

Please consider a door that size could possibly have 3 people standing on
it, but the door is only as strong as the frame it sits in

My thoughts would be to put a handrail around the openning so it cannot
be stood on

DG · Post by DG » Wed Oct 15, 2008 2:47 pm

That's exactly what I would prefer as I have visions of my inebriated son falling down the stairs. However, he wants an 'open plan' room and so for the time being, until I can persuade him otherwise or he breaks his neck, a strong loft hatch is the compromise. If/when I come to sell the house I will put up a handrail.