Loft insulation in Freshwater and Totland

There is no single right product, only a right one for the roof you have. Rolls of mineral wool, sold as glass wool or as rockwool, do the long open runs and are what most lofts get. Batts suit a roof cut into small bays by truss bracing, because a batt drops in where a roll has to be fought. Loose fill goes into a shallow pitch and into the awkward corners that nothing else reaches. Sheep wool is there for anyone who would rather not handle mineral fibre. Rigid board, PIR or Celotex, belongs against the rafters rather than on a floor, and multi-foil quilt earns its place only where a sloping ceiling has almost nothing to give away.

Whatever the product, it goes down in two layers. The first sits between the joists. The second is turned and run over the joists, which buries the timber and takes away the cold strip it would otherwise leave in every ceiling. The pair come to roughly 270mm, the depth the Approved Document expects of a loft being renovated. What you are buying with it is a lower U value over the ceiling, which is where the largest single share of a house's heat loss goes, so it shows up on the heating bill and again on an EPC.

Where it does not go is into the eaves. Insulation finishes on the wall plate and the air gap above it is left alone, because that gap is how the roof takes a breath. Vent trays clip between the rafters to keep it open. Cross ventilation then takes the damp air up and away under the ridge, with a ridge vent making it quicker. A breathable membrane under the tiles gives a roof a second route out. Old bitumen felt underlay gives it none, so on those the eaves are the whole system. Insulating a ceiling lifts the dew point into the space above it, and a blocked eaves then turns into condensation, wet material and black mould on the timbers.

Before any of that, the old layer is dealt with. If it has settled thin, been compressed under a deck, gone patchy round the wiring, picked up droppings or is contaminated in any other way, it comes off the ceiling and into bags, and the bags go in the van. Anything missing at the edges tells its own story. It is not covered over, because a poor layer sealed underneath a good one is where interstitial damp collects. Crawl boards go down first, access is the hatch and nothing else, and the whole job counts as work at height, so the ladder is footed and the loft is lit properly.

The last hour goes on everything else up there. The cold water tank is lagged and its pipework with it, since the roof space is colder after the job than it was before. Wiring and cables are lifted onto the insulation. Fire rated covers go over recessed lights and downlighters. Nobody has to lose their storage either: legs lift the deck above the finished depth, the boarding is screwed back to them, and the loft ladder is reset to reach the platform. The hatch takes a board and a draught seal round the frame. Where the roof is already a room the whole job moves up to rafter level instead, with board between the rafters, an air path kept above it, taped vapour control on the room side, and a warm roof over the deck where the covering is coming off anyway.

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 Victorian cottage with a small hatch over the stairs, a post-war bungalow with a wide open loft, and a top floor flat with the hatch on a shared landing are three different mornings before any material is opened. 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 Freshwater, Totland, Colwell and the PO40 addresses around them, with the Isle of Wight Council for 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.