Loft insulation in Bearwood

Two layers, and the second one crossways. A ceiling joist is not deep enough to hold what a ceiling needs, so a single layer laid flush between the joists leaves you a third of the way there with every timber acting as a cold bridge. The first layer goes between the joists. The second is laid across and over the joists at right angles, bringing the total to around 270mm, which is the depth behind the U-value Part L expects. When it is right there are no joist tops visible anywhere in the loft.

What goes down. Mineral wool for most jobs, as a glass wool roll or a firmer rockwool batt. Loose fill where the joists are at odd centres or a trussed roof is too tight to work a roll into. PIR rigid board where headroom is short, cut tight and taped, and a multi-foil quilt where even board will not fit. Sheep wool if you would rather. What is already there stays if it is dry and even, and comes out bagged if it is damp, patchy, missing at the edges, settled and compressed to nothing, or contaminated with droppings.

The eaves, which is where lofts are ruined. Insulation goes out to the wall plate and no further and the air path past it stays open. Vent trays hold a clear air gap under the felt so cross ventilation carries on from one side to the other, and where a roof cannot breathe at the edge a ridge vent is sometimes the answer instead. A breathable membrane changes the detail but not the principle. Push wool hard into the eaves and the vapour that used to leave the roof space condenses on the underlay instead. You get wet insulation, black mould on the rafters and, in time, soft timber. Insulating moves the dew point, and interstitial condensation inside the layer is the failure nobody sees until the ceiling stains.

Electrics, pipes and the hatch. Recessed lights get proper covers, not wool piled over them. Cables come up above the new layer rather than under it, because wiring buried in insulation runs hot and has to be de-rated. Any cold water tank and its pipework now sit in a colder space and want lagging, with the area under the tank deliberately left thinner. The hatch gets a board of insulation on its back and a compression seal, because an unsealed hatch is a hole in the ceiling and a draught you can feel on the landing.

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. An eighties semi with a small square hatch on the landing, a detached house with half the loft already boarded and full, and a terrace where a loft ladder has to come down into a narrow hall are three different mornings, and the climb is work at height before the job even starts. 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.

Getting on for three in ten homes here are terraced, with plenty of semis besides, and that puts a separating wall somewhere above your ceiling. In most of them it carries on up through the roof space to the underside of the tiles, so your loft genuinely ends there and your neighbour's begins on the far side. We insulate to that line and no further, and nothing we lay is allowed to sit against it in a way that interferes with the separation.

The practical points are small and they matter. The corner where that wall meets the eaves is the tightest spot in the whole roof and the one most often left bare, so it gets filled by hand rather than by pushing a roll at it. If there is an open cavity at the top of the wall, that is a route for cold air to arrive above your bedroom ceiling and it wants closing. And if the row went up as one job, whatever is wrong in your loft is usually wrong next door, which is worth a word with a neighbour. On an EPC the loft is the one item an assessor measures rather than assumes, and on the heating bill it is the first thing that moves.

We cover Bearwood, Kinson, Longham, Merley, West Parley and Broadstone, and the BH11 addresses around them, with BCP Council for both 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.