Loft insulation in Redlynch

Boarding is where most of these jobs go wrong before anybody touches the insulation. Chipboard screwed straight down onto the joists crushes the wool underneath to a fraction of its thickness, and the bit you crush is the bit over the room you actually use. So the storage comes up on loft legs, a raised floor sits clear above full depth, and the platform is put where you need it rather than everywhere. Most houses want a deck by the hatch and nothing else, and the loft ladder gets checked so it still lands properly once the floor level has changed.

With that decided the rest follows in order.

Clearing. Anything contaminated with droppings, anything that has been wet under a slipped tile, granular loose fill that has drifted into the corners and old quilt that has broken down into dust all come out. Sound material that is merely compressed and patchy is worth keeping, so it gets teased apart, straightened between the joists and covered over. It is dirty work, it takes a while, and you cannot lay an even depth over an uneven base.

Depth, in two directions. The first layer goes between the joists, friction fitted with nothing open at the sides. The second is cross laid across the joists, which buries the timber so it stops working as a cold bridge into the plaster below. Miss that and you have paid for half a job. Around 270mm finished is the depth a renovated ceiling needs to reach the U value in Approved Document L under Part L. Mineral wool roll for the long runs, rockwool batts where hand cut joists put every bay at a different width, glass wool, sheep wool, or loose fill where bracing leaves no other way in.

The eaves, then the fittings. Insulation is carried out over the wall plate and stopped, a vent tray at each rafter keeps an air gap open above it, and cross ventilation runs on from one soffit to the other. Older roofs out here often carry no underlay and breathe on their own; where one has been re-covered with a breathable membrane or the soffits have been boxed in, that path narrows, the dew point shifts into the structure and interstitial condensation shows as damp wool, water on the felt and black mould over the timbers. A ridge vent or tile vents deal with it where the eaves cannot. Then fire rated covers over recessed lights and downlighters, cable and wiring lifted clear so nothing runs hot, lagging on the cold water tank and its pipework, the hatch insulated on its back and draught sealed round the lining. Where the roof is already a room in roof with a sloping ceiling and a dormer, it becomes a warm roof at rafter level instead: PIR rigid board such as Celotex between and under the rafters, taped vapour control layer, multi-foil where there is nothing left to give.

No rate per square metre, because the floor area is the easy part and the awkward edges are where the time goes.

Getting to it. A bungalow with the hatch in the hall, an older cottage with a loft full of material that has to come out, and a chalet with rooms already in the roof are three different jobs. A hatch on a landing you can stand a ladder under is one job. A hatch over a stairwell, a crawl space you can only move through on your knees, or a loft full of boarding that has to come up and go back, is time before any material is laid.

What is up there now, and what it is sitting on. Old material that has to come out, be bagged and taken away is a cost before anything new goes down, and so is a loft full of boxes that has to be emptied and put back. Joists at 400 centres with a flat run across them is a different afternoon from a trussed roof full of bracing.

Ventilation, and the edges nobody reaches. Insulation stops at the wall plate and the eaves have to stay clear, or you trade a warm bedroom for a wet roof. Getting depth right into the corners and around the hatch, boxing over downlighters and lagging anything that now sits in the cold, is most of the labour. Approved Document L sets what the work is expected to reach.

Comparing quotes? Ask what depth is actually being laid and in how many layers, whether the old material is coming out or being covered over, whether the eaves are being kept clear, what happens to anything you store up there, and whether the hatch and the pipework are included. Two quotes for the same job are usually two different jobs.

We cover Redlynch, Morgan's Vale, Woodfalls, Downton, Landford and the SP5 addresses around them, with Wiltshire Council for planning and building control. You are dealing with Bournemouth Roofing & Building, the trading name of Bournemouth Roofing & Building Ltd, registered in England and Wales, company number 15471719, which you can look up in a minute. Thomas Hannen's business, and he is the one who comes out to price the job, not a salesman. A verified customer's 10 out of 10 on Checkatrade. The visit and the written quote are both free.