Loft insulation in East Boldre

Start with what is there. Most lofts here have something in them and almost none have enough. It has settled and compressed under forty years and anybody who knelt on it, it is patchy across the middle and missing at the edges, and there are gaps where cables and pipes come through. Dry and in one piece it stays, and the new layer goes over it. Damp, black underneath or contaminated with droppings, it comes out, gets bagged at the hatch and leaves with us.

What we lay. Mineral wool covers most of it, usually a glass wool roll, sometimes a rockwool batt, and on irregular joists it gets cut to the bay rather than forced in. Loose fill, blown or poured, suits a ceiling that will not take a roll. Sheep wool if you prefer it. Where headroom runs out, PIR rigid board cut tight and taped, and in the shallowest corners a multi-foil quilt.

Two layers, and the second crossways. One layer laid flush between the joists is where most lofts stop, and it leaves every timber acting as a cold bridge through the ceiling. The first layer goes between the joists. The second is cross laid at right angles, covering the joists as well as the bays, and around 270mm all in puts a ceiling where the Part L U value expects it to be. Finished, there should be no joist tops showing anywhere.

The eaves decide whether it works. The material runs to the wall plate and halts and the air path past it stays open, with a vent tray in each rafter bay to keep the air gap so the roof can cross ventilate from one wall plate to the other. Push wool into the eaves and the vapour that used to leave the space condenses under cold felt instead. The dew point moves into the layer, interstitial condensation forms where nobody can see it, and you end up with damp wool and black mould right across the rafters. Approved Document F sets the ventilation standard, and where the eaves cannot be opened a ridge vent is often the honest answer. A breathable membrane changes the detail, not the principle.

Services, hatch and rafter level. Rated covers go over the recessed lights so nothing sits against a hot fitting, and cables are lifted onto the top of the new depth, since buried wiring runs hot. A the cold water tank and every pipe serving it now sit in cold air, so on goes the lagging. A board goes on the back of the hatch and a seal round the opening against draughts. Where there is no loft floor to work on, a room in roof gets its insulation at rafter level in a warm roof build up, with the sloping ceiling and any dormer cheek carried through as one continuous layer.

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 single storey cottage with a small trapdoor, a chalet with rooms already in the roof, and a house with a hatch over the stairwell are three different mornings. The access is work at height and gets treated that way. 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.

Everything we do on a loft floor here is invisible from the lane, so the designation over this village has nothing to say about it. Depth, material, boarding, a sealed hatch, lagging on the pipework: none of it is development and none of it needs consent. If anybody tells you the National Park stops you insulating, ask which part of the designation they mean.

The line moves the moment you want to live in the space rather than store things in it. A loft conversion adds rooflights or a dormer, and inside the National Park permitted development rights are drawn more tightly than they are a few miles away, so a dormer that would be waved through elsewhere is a planning application here. The same applies to a run of vent tiles or an over fascia vent if the honest fix for a roof that cannot breathe is to open it up. Our advice is to keep the two apart. Get the loft floor to full depth now, because it is cheap, quick and nobody's decision but yours, and treat anything that changes the outside of the roof as its own separate question.

We cover East Boldre, Pilley, Boldre, Portmore, Norleywood and the Lymington side of the forest, and the SO42 addresses around them, with the New Forest National Park Authority for planning and building control through New Forest District Council. 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.