Advice required for boarding out a loft (with down-lights)

[mjgreen81]

Hi all,


I am currently planning out the boarding/insulating of my loft. We have downlights in a couple of the bedrooms so I want to make sure everything is safe with regards to keeping them away from the insulation.

My joists are 35mm wide and 90mm high - the spotlights stick out about another 20mm above this (so 110mm in total).

I also have cables trailing above the joists.

I have had a look online and found these downlight insulation guards from Screwfix which are 140mm high.

http://www.screwfix.com/p/halolite-downlight-insulation-guard-220mm/97932

The only thing I can think to do is to install batons along the existing joists to raise the level above the 140mm insulation guard (and leave gaps for the cables). This means batons of 35mm wide by (at least) 50mm high.

I had a look in B&Q yesterday and the closest I could find was 38mm x 63mm which seemed to be a standard size. However, the reality of looking at this size timber made me realise that 63mm is quit a high/ narrow thing to screw through!

Is this the best way to achieve what I want? Or am I looking about this the wrong way?

Many thanks

 

[Newboy]

38x63 is standard cls sizing.

Screw the cls to the existing joist and then & screw the flooring to the cls - don't try to screw all the way through in one go that's just making life difficult for yourself!

 

[mjgreen81]

- It certainly would be!

So it sounds like I am going around this the right way. I just need to get some fairly long screws to go through the 63mm length.

 

[Newboy]

New timbers at 90° to the existing joists and fix them so that the centres are correct for the board widths. Pilot drill the new timber to a) prevent splitting b) is the correct way to do it and c) it make life easier for yourself.

Before you screw them to the joists check for cables and pipe running through.

 

[mjgreen81]

New timbers at 90° to the existing joists and fix them so that the centres are correct for the board widths. Pilot drill the new timber to a) prevent splitting b) is the correct way to do it and c) it make life easier for yourself.

Before you screw them to the joists check for cables and pipe running through.

Thanks for your reply.

Why do you say about fixing the new timber at 90degrees to the existing joists?

Is this preferential to fixing them directly on top of the existing joists?

 

[Newboy]

1) It's a lot easier
2) It means that you can get your centres spot on and square for the boarding
3) It spreads the load across more than one joist
4) Much easier to avoid cables and pipework
5) The insulation will be better as the existing joists tops will be covered

 

[DeadBeat]

if this post works it should have some pics as to how i raised the floor level in my loft and doubled the insulation thickness, If you click the little white up arrow next to "deadbeat said:" below, it will take you to the origional post where the photos are expanded

The Third big project was to re insulate and floor the loft space so we could move stuff into the loft and out of the way

View attachment 88239 View attachment 88240 View attachment 88241View attachment 88244 View attachment 88246 View attachment 88247 View attachment 88248 View attachment 88249

 

[mjgreen81]

Thats great, thanks Deadbeat.

I had another look up in the loft earlier and realised that there are already a few original 4" x 2" joists (not sure how I missed this) going at 90 degrees to the main joists which the ceiling is attached to. I presume they are there for the extra strength (there is 1 going across the centre of the first area I want to board). It now makes sense to utilise these and bring the floor up to the this level so instead of using the 38mm x 63mm batons, I think I will get some 100mm x 47mm (the closest I can find to 4" x 2") and place these in the appropriate position for the loftboards.

My one question is, what is the best way to go about attaching the 100mm batons to the existing joists? Do I need some seriously long screws or should I screw diagonally? (the existing 4" high joists are nailed in diagonally)

 

[mjgreen81]

After discovering that it looks like the 100mm x 47mm timber looks like it is only available for delivery (4 days) from B&Q, I think I might have answered my own question...

I guess I could screw in a 50mm x 47mm timber to the original joist, and then screw in another 50mm x 47mm timber on top of this bringing me up to the 100mm.

I presume that would be ok?

 

[DeadBeat]

google howarth timber, they will usually be able to do next day and are a lot cheaper than B&Q plus i believe over a certain amount and delivery is free, just find your closest branch, travis perkins will also probably be cheaper than b and q and will also deliver for free next day if over an amount but i think howarth will be cheaper than them.

what i did was setup my drill and got a wood bit ( a decent one not one of those flat things, one thats more like a corkscrew), then i setup the stop on my drill so i drilled about halfway through the wood, i then took some of the self drive wood screws 100mm i think maybe 120mm and drilled them in with an impact driver (made the job so much easier having one of these i can tell you)

you could get extra long screws to do it, but i imagine they would be quite expensive

it took time to pre drill every hole for every screw but the fix is absolutely solid

 

[roboughton]

Local timber yard is going to be alot cheaper than BnQ that's for sure. I would also pre drill the holes somewhat with the length you need to screw into. the other option is to go in at a angle to screw to both bits of wood but that is not ideal as you could push centres out doing it that way.

 

[mjgreen81]

Thanks guys, some great tips there. Will hopefully get cracking with the job tomorrow