Spacing loft beams

|In order to be able to board an area of my loft after having insulation |fitted I am placing 4x2s at right angles to the existing ones. What is |the spacing between centres to fit the standard insulation please? I |cannot use the existing ones as a guide because their spacing varies |from 13 to 19 inches. Thanks

I just put chipboard on top of the beams. No problems in years

Can't quite figure out what you're doing here. Might have the wrong end of the stick but... Why do you need extra 4 x 2s? Lay the insulation between the joists and fill in with offcuts if necessary. Use polystyrene pellets if it's easier. If you're using the packs of chipboard flooring, you'll be very lucky to get them to line up lengthways, but you can always put them at right angles to the joists. More cutting and more waste but often there isn't another way. Better to use 8ft x 2ft T&G if you can get it up into the loft

The message from Broadback contains these words:

Work to the spacing needed for the boards instead, it'll save a lot of work.

Stuart Noble wrote: ...

Why bother with T&G? If it's only for occasional access for storage, minor gaps aren't going to hurt, and it makes it easier to lay and to lift sections later. I used plain 8x4 sheets of floor-grade chipboard cut down by the supplier into 1/2 width - they /just/ went through the hatch (check before buying :-) ). Much cheaper than T&G would have been.

Thanks for all your replies. The loft was floored with T&G when I moved in, however there is no insulation, so have have taken it up. In order to have the correct depth of insulation laid and then replace the T&G I am going to add the beams so that it is not compressed and lose its effect. anyway 16" it will be, cheers.