Loft insulation in Blandford Forum

Trussed roofs, and what can be done in them. Anything built here from the late sixties on will have a trussed rafter roof: shallow ceiling joists, timbers at close centres and diagonal bracing running everywhere. You cannot move about freely and you should never cut a truss. It changes the method rather than the result. Material goes in from the hatch outwards in smaller lengths, and the second layer is laid across the bracing rather than lifted over it.

The old layer, and whether it stays. Most of these Blandford Forum lofts already have something. It has usually settled to well under the depth it went in at, gone patchy at the edges and been pulled back in gaps for cables. If it is dry and clean we straighten it and keep it. If it is wet, compressed into the ceiling or contaminated with droppings, it comes out in bags and leaves with us before anything new is laid.

Material and depth. Mineral wool does most of it, glass wool or rockwool in a roll, the first layer cut to a friction fit between the joists and the second laid across them at right angles to 270mm finished. Batts are quicker where trusses are at odd centres, loose fill goes where nobody can crawl, and rigid board such as PIR or Celotex is for the places headroom will not allow a roll. Multi-foil and sheep wool are for the exceptions, not the rule.

The eaves, and the party wall. Insulation stops at the wall plate, and on a shallow truss that is exactly where somebody is tempted to stuff it. We hold the gap open with vent trays so air still crosses the loft under the felt. On a Blandford Forum terrace or semi the party wall is the other cold edge, and getting depth right into that corner matters more than another pass across the middle. A breathable membrane is kinder than old felt, and a ridge vent helps where eaves cannot be opened.

Storage, and the hatch. A trussed loft is not a store room, but people use them anyway. Boarding laid flat on the joists crushes the wool and wastes the work, so we build a raised floor on loft legs over a defined area and board that, keeping full depth underneath and the loft ladder usable. The hatch itself gets insulated on the back and draught sealed, which is the part most quotes never mention.

Services and sloping ceilings. Any cold water tank and its pipework get lagging once the ceiling below is warm and the loft is not. Cables are lifted and clipped over the top rather than buried, because wiring that cannot shed heat carries less current, and every recessed light or downlighter gets a fire rated cover. Where a room in the roof or a dormer already exists, the work follows the rafters instead: board between them with a clear gap to the underlay, a layer under, joints taped.

The floor area of a loft is simple. The tight edges are what take the time. The way in. A hatch over the stairwell in a terrace, a wide landing hatch in a semi, and a hatch reached from a shared landing in a block of flats are three different starts before a roll is opened.

What is already there. Compressed or damp old material is taken out and bagged. Stored boxes and boarding have to be moved and put back.

Joists and trusses. A loft with open joists at 400 centres is quick to lay. Trusses crossed with bracing, common on the town's later estate houses, slow each roll.

Flats. In a block, the roof space is usually part of the common parts, so the freeholder instructs the job and the price may be split between the flats.

The edges. The insulation must stop short of the wall plate so air still flows. Pushing full depth into the corners, boxing over downlighters and lagging pipes takes most of the labour.

Another firm's price should say how deep it goes and in how many layers, what happens to the old wool, how air will still reach the eaves, and whether the hatch and pipes are part of it.

Blandford Forum is a 16.8 mile run up from our base in Boscombe. For lofts we cover the town, Bryanston, Stourpaine, Spetisbury, Winterborne Stickland and the Tarrant villages, and building control there is Dorset Council.

Bournemouth Roofing & Building Ltd, the company you would be dealing with, is registered in England and Wales, company number 15471719. The owner, Thomas Hannen, gets into the loft himself and works out the price. A verified Checkatrade customer scored us 10 out of 10. No charge is made for visiting, and your written quote, listing each item, is free. Before you book a visit in Blandford Forum, you can read our customers' Google reviews, word for word, on our reviews page.

Most repairs in Blandford Forum need no application at all. What decides whether a change to the outside of your house does is who the council is, whether a conservation area or a listing applies, and whether the place sits in a protected landscape.