Wall insulation in Westbourne

Finding out what the wall is. The late Victorian villas are mostly solid brick, often nine inch, though some later houses have an early narrow cavity, and from the street you cannot tell which. The post-war blocks have cavities, and many built from the 1980s onwards had insulation built into them.

One small hole drilled in a mortar joint and a look through a borescope settles it: whether there is a gap, how wide, whether it is clear and dry, and what is in it already.

Internal wall insulation in a flat. This is the job most Westbourne leaseholders can actually do. The cold wall is lined from inside: insulated plasterboard bonded to the brick, or battens or a stud frame with PIR or mineral wool between, boarded and skimmed. Celotex and Kingspan type boards give the most for the thickness, which matters in a converted room with cornices and a bay, and an aerogel board suits a wall that cannot lose much depth. The heat goes at the edges, so the window reveals, the floor junction, the ceiling line and the joist ends are wrapped too, and that is where most of the labour sits. A single room is usually two or three days, with plastering and making good after.

Breathable linings on old brick. A solid brick Westbourne villa wall has taken rain in and let it out again for well over a century. Close it with a foil faced board and a sealed membrane and the moisture has nowhere to go but the new plaster and the timber in the wall. On those walls we lean towards wood fibre or a mineral board set in a lime based adhesive, which gives a little less insulation for the thickness and keeps the wall drying, in line with BS 5250 on managing moisture in buildings.

Cavity fill on the blocks. Where a Westbourne block has a clear, dry cavity, cavity wall insulation is blown in from outside through holes drilled in a pattern across the mortar joints, usually bonded bead on a wall that takes the weather, and the holes are then made good. It is specialist work and should be done by a registered installer who issues CIGA paperwork for the fill. What we bring is the survey before it and the repairs it depends on, because filling a cavity behind cracked render or open joints on a seaward face lets driven rain cross to the inside. If an old fill has slumped or got wet, it has to be extracted by specialists before anything else goes in.

External wall insulation. EWI, board with a render carrier and a thin coat finish, wraps a whole building and deals with the thermal bridge at every floor slab, which suits a plain rendered block. It is a whole-building decision taken by the freeholder, it thickens every reveal and moves every downpipe, and on the shopping streets it runs into the conservation area.

Ventilation. Insulating shifts the dew point and stops the draughts that were drying a Westbourne flat, so trickle vents, a working bathroom and kitchen extract and clear air bricks are part of the job, and an internal lining gets a taped vapour control layer so interstitial condensation stays out of it. Heat loss drops, the EPC improves, and the payback shows in how the room feels first.

When we would talk you out of it. If the mould is from drying washing indoors with no extract, a fan fixes it for far less. If the wall is wet from a broken gutter, fix that first.

No rate per square metre, because the wall area is the easy part; what happens at every window, door and floor junction is not.

Getting to it. A second floor flat in a converted villa with no lift, a flat above a shop on the Poole Road pavement, and a purpose-built block with a car park round it are three different set ups, and on a pavement frontage a scaffold needs a council licence under section 169 of the Highways Act. Cavity fill is drilled from outside and a bungalow comes off a tower where a three storey gable wants a scaffold. Internal lining is worked room by room from inside, so it is your rooms rather than a platform that gets disrupted. The work at height rules still set the platform.

Which wall you actually have. A cavity that is clear and dry can be filled in a day. A solid wall cannot be filled at all, and has to be lined inside or insulated outside, which is a different job at a different price. A borescope through one drilled hole settles it, and no honest quote is written before that.

The junctions, not the field of the wall. Reveals at windows and doors, the floor junction, the eaves and any party wall are where heat escapes and where condensation shows up if the detailing is wrong. That work is slow, it is most of the labour, and it is the first thing a cheap quote leaves out.

Comparing quotes? Ask whether the wall has actually been checked with a borescope or just assumed, what system and what thickness is specified, how the reveals and floor junction are being detailed, whether ventilation is being addressed, and who makes good the plaster and decoration afterwards.

We cover Westbourne and the rest of BH4, from County Gates along Poole Road and Seamoor Road towards Alum Chine, with Branksome and Canford Cliffs next door. BCP Council handles planning and building control, and our Boscombe base is under three miles away.

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. Before you book a visit in Westbourne, you can read our customers' Google reviews, word for word, on our reviews page.

Most repairs in Westbourne 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.