Wall insulation in Lilliput

Looking inside the wall comes first. We drill one small hole through a mortar joint and put a borescope camera in. It shows straight away if there is a cavity at all, how wide it is, whether rubble and mortar have dropped in and bridged it, and whether anyone has filled it already.

From a Lilliput drive a nine inch solid brick wall and a brick and block cavity wall can look identical, and behind render there is no telling. We also take moisture readings indoors, and look at the pointing, the sills, the gutters and the direction each elevation faces.

Cavity fill. A clean, dry Lilliput cavity in sound brickwork that is not badly exposed to driving rain can take a blown fill of bonded bead or mineral wool through a drilled pattern of holes. That is carried out by a separate cavity wall installer rather than by us, and you should keep their paperwork with the deeds. Before any fill, the pointing, cracked render, leaking gutters and blocked air bricks want putting right, and we will tell you which of those your wall needs.

Lining a room from inside. When a Lilliput wall is wrong for a fill, or only one room is the problem, the insulation goes on the inside face. The slimmest option is insulated plasterboard, a board bonded to PIR from makers like Celotex or Kingspan. Where a solid wall has to keep drying, a timber stud or battens packed with mineral wool is the breathable choice. The awkward bits get the care: window reveals, the joint with the floor and the joist ends, because any strip left bare becomes the cold bridge where condensation settles. Expect a few days a room, skim coat included.

Cladding the outside. External wall insulation, EWI, makes most sense when the render is due for renewal. Boards are fixed over the brick, a render carrier and mesh go over those, and a thin coat render finishes it. Because it wraps the house in one layer it deals with the thermal bridge at every floor edge and corner, and it takes the rain off the brickwork, but the sills, the pipes and the eaves line all have to come out to meet it. The whole elevation goes under scaffold.

Fill that has gone wrong. Some older fills in Lilliput have slumped, leaving the top of the wall empty and cold, and some carry rain across the gap, so the inside wall shows damp. A wet cavity must be cleared before anything else is tried. Extraction is specialist work, and if the camera shows it is needed we say so plainly.

Air still has to move. Stop the draughts in a Lilliput house and you also stop what was drying the room. We check trickle vents, kitchen and bathroom extract fans and air bricks as part of the job. What you notice first is heat staying in the room overnight, and the EPC rating follows.

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 house with every wall reachable from its own drive off Lilliput Road, a gable on the slope above the harbour that needs a scaffold on stepped ground, and a flat in a block where the walls are shared with the other owners each set the day up differently. 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 work on walls across Lilliput and the rest of BH14, along Sandbanks Road and Lilliput Road to Evening Hill and Salterns, and on to Whitecliff, Canford Cliffs and Penn Hill, from our base in Boscombe, about five 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 Lilliput, you can read our customers' Google reviews, word for word, on our reviews page.

Most repairs in Lilliput 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.