How much does loft boarding cost?

It depends on the loft, so anyone quoting a figure before they have seen it is guessing. What moves the price is the floor area, how you get up there, the size and condition of the existing ceiling joists, how much insulation is already down and how deep it is, whether the hatch needs enlarging, and whether a ladder is going in at the same time. A small square loft with easy access and a decent hatch is a straightforward job. A cut roof full of struts and purlins, or a hatch too small to get boards through, is not. Send photos and you can have a sensible answer rather than a number plucked out of the air.

Can you board over loft insulation?

Not directly onto it, no. Insulation only works while it is full of trapped air, and laying boards straight down on top squashes it flat — you lose a good part of the insulation value you paid for, and you trap moisture against the boards. The right way is to raise the floor above the insulation so the insulation keeps its full depth and air can still move around it. That is what the new timber does on a job like this.

How do you board a loft with insulation already down?

You add depth. On this job a new set of 4x2 C16 joists was run across the existing ceiling joists, which lifted the floor level and left a clear space underneath. The insulation sits in that space at its proper depth, and the boards go on top of the new timber without ever touching it. The floor ends up higher than the old ceiling joists, which is the trade-off — you need the headroom for it.

Can loft boarding be raised above the insulation?

Yes, and for most lofts it is the only sensible way to do it. Raised loft boarding means the boarded floor sits clear of the insulation on new timber rather than crushing it. It costs a bit more in materials and it eats some headroom, but it keeps the insulation doing its job and gives you a stronger floor at the same time.

Can a loft ladder be fitted at the same time as loft boarding?

It makes sense to do both together. The hatch usually has to be opened up for a ladder anyway, and you want the boards and the ladder set out around the same opening rather than fitting one and then cutting into the other later. On this job the hatch was formed, the opening boarded out and trimmed, and a timber folding ladder fitted as part of the same visit.

Loft Boarding in South Kirkby

Finished boarded loft floor in South Kirkby, 18mm chipboard laid over new timber joists for storage — The finished loft floor — around 27 square metres of proper storage space.

Most lofts are wasted. There is a hatch you can barely get your shoulders through, a few boards laid loose over the insulation, and a load of stuff balanced on top that nobody wants to go near. This one in South Kirkby was no different when we started.

The job was loft boarding and loft ladder installation together: a new timber floor built over the existing ceiling joists, more insulation laid in, 18mm chipboard flooring over the top, and a timber folding ladder so you can actually get up there. It came out at roughly 27 square metres of usable storage.

Loft in South Kirkby before boarding, with insulation between the existing ceiling joists — Before anything went in — insulation between the ceiling joists and nothing to stand on.

Creating a loft storage floor

Here is the bit that gets missed. The timbers you can see in an ordinary loft are ceiling joists, not floor joists. They were sized to hold up a plasterboard ceiling and not much else. They are not there to carry you, a few hundred kilos of boxes and a chest freezer full of last Christmas.

So the floor gets built, not just covered. New 4x2 C16 structural timber was run across the existing ceiling joists, picking up bearing at the walls, to form a proper floor deck above the old ones.

New 4x2 C16 timber joists running across the existing ceiling joists to form a loft floor — New 4x2 C16 running across the existing ceiling joists — a floor in its own right.

Running the new timber across the old rather than alongside it does two things at once. It spreads the load over a lot of joists instead of concentrating it on a few, and it lifts the floor level clear of what is already down there. That second point matters more than people expect, and it is what the next section is about.

New loft floor joists installed across a South Kirkby loft ready for boarding — The new floor joists in and levelled across the full span.

Noggins went in between the new joists. They stop the timber twisting as it dries out and they stiffen the whole deck, so the finished floor feels solid underfoot instead of springy. It is a small amount of extra work that you feel every time you walk on it.

Timber noggins fitted between new loft floor joists to stiffen the deck — Noggins between the joists — they stop the timber twisting and take the spring out of the floor.

Loft boarding over the existing insulation

This is where a lot of loft boarding goes wrong, and it is worth understanding before anyone starts.

Insulation works because it is full of trapped air. Squash it and you throw a good part of that away. Lay boards straight down onto insulation that is already at the right depth and you have just flattened it, and paid for the privilege — you get a floor and you lose insulation you already own.

Raising the floor on new timber solves it. The new 4x2 sits above the old ceiling joists, and the gap that creates is where the insulation lives, at full depth, with the boards never touching it.

Loft insulation laid between new floor joists before the chipboard flooring goes down — Insulation laid into the depth created by the new timber, before any boards went down.

Because the new timber had created that depth, more insulation went in while the floor was open. That is the sensible time to do it — once the chipboard is down and screwed, getting back under it is a job in itself.

18mm chipboard loft flooring

The floor was decked in 18mm chipboard flooring, laid across the new joists and screwed down.

Chipboard flooring is the right material for a storage loft. It is stable, it comes in big sheets so there are fewer joints, and at 18mm over joists at sensible centres it gives you a floor you can load up and walk about on without it flexing.

18mm chipboard loft flooring being laid over new timber joists in South Kirkby — Most of the deck down and ready for the final screwing off.

Boards get laid with the joints landing on timber, staggered rather than lining up in a row, and screwed rather than nailed so nothing works loose and starts creaking later. No shortcut workmanship — a loft floor that squeaks every time you cross it is a floor that was rushed.

Fold-down loft ladder installation

A boarded loft is no use if you still have to fetch a stepladder and haul yourself through a hole every time you want something.

The hatch was formed and the opening boarded out and lined properly, so the edges of the new floor are finished rather than left as raw board ends around a hole.

Loft ladder opening boarded out and lined in a South Kirkby loft — The opening boarded out and lined, ready for the hatch and ladder.

New loft hatch formed and fitted in a South Kirkby home — The new hatch formed and hung.

Then the timber folding loft ladder went in, fixed to the hatch door so it drops down into the landing and folds away flat when it is not wanted.

Timber folding loft ladder installed and pulled down into a landing in South Kirkby — The timber folding ladder down and ready to use.

Setting a ladder out is not just screwing it to the hatch. It has to land in the right place on the landing floor, at a sensible angle, clear of the walls and of anything on them, and it has to sit square so it folds away without fighting you. Get that wrong and you have a ladder nobody uses.

Finally the hatch was trimmed with architrave, so from downstairs it reads as a finished part of the house rather than a hole in the ceiling.

Loft hatch trimmed with architrave and finished from below — Architrave round the hatch — finished from below, not just functional from above.

Loft boarding is not a loft conversion

Worth being straight about this, because the two get mixed up and they are very different jobs.

What was built here is a storage floor. It is strong, it is properly insulated underneath, and it will take a serious amount of gear. It is not a room. A loft conversion is a different piece of work altogether — structure, stairs, headroom, escape, insulation and fire all have to be dealt with, and it goes through building control.

Most people asking about loft boarding do not want a conversion. They want the boxes, the tools, the camping gear and the Christmas decorations out of the spare room and somewhere sound to put them. That is exactly what this is, and it is a fraction of the work.

The floor structure itself is ordinary first fix carpentry — setting out, joists, noggins, decking — the same thinking that goes into any timber floor, just done in an awkward space with a roof over your head.

Loft boarding and loft ladder fitting in South Kirkby

The finished loft gives roughly 27 square metres of boarded storage, a floor built to be loaded rather than tiptoed across, insulation kept at full depth underneath it, and a ladder that makes the whole thing worth having.

Heritage Joiners carries out loft boarding, loft storage flooring, raised loft floors and loft ladder fitting around South Kirkby, Pontefract, Wakefield and the wider West Yorkshire area.

If you want your loft boarding out for storage, send Rob a few photos — the loft itself, the existing hatch, and the landing below it — and he will give you an honest first view on what it needs before arranging a visit.