Wall insulation in Holt
You cannot read a wall from the road out here, so one small hole and a camera settle what can be done long before anything is specified.
The site visit is free and so is the written itemised quote. Thomas Hannen prices every job himself.
Last updated
A Holt wall can be filled only if a borescope shows a cavity that is clear, dry and not already full; a solid wall has to be lined, and a wet one has to be dried first. There are things you can usefully check yourself before ringing anybody, and it is worth knowing in advance where each of them runs out. Render, pebbledash, paint and later extensions all hide brickwork. A house that reads Victorian from the lane may have a 1970s cavity behind the finish; a house that reads modern may be a rendered solid wall. So around Holt the survey is not a formality that precedes the quote. It is the thing the quote is made of.
The signs in Holt are ordinary enough. A room that never quite warms up. A wall cold to the back of the hand. Black mould in the same corner every winter. Damp patches on an outside wall that come and go with the weather.
Then we drill a small hole in the Holt wall and feed a borescope in. Out of that comes whether a cavity exists, how wide, how clean, how dry, and whether anyone has blown anything into it already. Solid walls get their thickness measured, and the plaster, the reveals and the joist ends read over. There is no charge for the visit, and none for the itemised quote written afterwards.
Before you ring anyone
Six checks you can make yourself, and where each one gives up
The first check is a window reveal. Deep, and the wall beneath the finish may be solid, a nine inch bond or thicker. Shallow, and a cavity becomes likely. It gives up at a replacement frame, set forward in the opening, which shortens the reveal whatever lies behind it. Measure anyway: reveal depth decides whether an ordinary board fits at the frame or whether aerogel has to.
Two. Look for header bricks at a corner. On a Holt house, short ends every few courses point to a solid wall bonded through its thickness; stretchers all along point to a leaf with something behind it. It gives up the moment a wall is rendered, pebbledashed or painted.
Three. Sight along the mortar for a grid of plugged holes. Filled drillings roughly a metre apart mean somebody has pumped this Holt wall already. Not the end of the matter, though, because the live question is whether that material is still even and still dry. Slumped fill leaves a cold band under the eaves and a matching line of black mould inside.
Four. Find the build date, then distrust it. Extensions, rebuilt gables and rendered frontages mean one Holt address can honestly carry two kinds of wall on two elevations. Age is the least reliable of the six and the one people lean on hardest.
Five. Cold morning, back of the hand, every room. You are mapping which elevation of your Holt house is worst and where mould appears. Damp coming and going with driving rain is penetrating; damp arriving every winter in corners is condensation. The two want opposite work, and confusing them wastes money.
Six. Put your head into the loft at the eaves. On a bungalow or a low eaved house the top of the cavity is often visible from up there, along with whether fill ever reached it.
What none of the six settles. Whether anything can safely go into that Holt wall. A 12mm hole, a borescope, and the clear width, the snots on the ties, the slumped or wet fill are all in front of you. A bridged or wet cavity gives water a path to the inner leaf, so the outer leaf gets put right first.
If the camera finds a gap. Clear, dry, wide enough: drilled on a pattern, pumped, made good in a day. Bonded polystyrene bead runs round the ties and stays put. Blown mineral wool still works in a clean, sheltered cavity. Failed fill comes out and is vacuumed away first.
If it finds no gap. Internal wall insulation, IWI, means insulated plasterboard bonded on or a batten and stud frame packed with mineral wool; PIR laminate, Celotex or Kingspan, in the shallowest build up, or a breathable make up on older brick so the wall keeps drying, vapour control taped per BS 8000-8. External wall insulation, EWI, boards under a render carrier and a render finish, keeps your floor space and settles the joist ends and the floor junction together, at the price of changing the face of the building.
Either way, the junctions and the air. Reveals, threshold, floor junction, eaves, joist ends, and a cavity barrier at a party wall. A cold bridge, or thermal bridge, at any one of them collects condensation whatever the u value beside it. Then trickle vents, extraction discharging outdoors from kitchen and bathroom, air bricks left clear, to the expectation set by Approved Document F. Airtightness without a route out is how a warm wall makes a damp one.
How it runs
Wall insulation in Holt starts with a borescope
The walls come first. Thomas looks at what they are made of, the direction they face, the pointing and render, and whether the cavity holds anything. A single drilled hole and a borescope show what is inside.
The price that follows lists the survey with its borescope check, which insulation and at what thickness, the making good round windows and doors, any extra ventilation, and clearing up. If a fill is on it, the quote names a registered installer and the CIGA certificate you should receive.
Cavity fill is injected from outside, drilling from a ladder or tower. For a solid wall, the choice is lining it from inside, one room at a time, or insulating outside from a scaffold. Where an older solid walled part of a house has a newer cavity walled extension, the two halves are priced as separate jobs, because they are.
Drill holes are filled to match, rooms are sheeted and cleared as far as needed, and waste leaves with us. If the borescope finds rubble in the cavity or corroded wall ties, that is photographed and priced before anything goes in.
Holt is under Dorset Council, and there is no conservation area over the village. On a listed building, even internal work can need listed building consent. For everyone else it is building control, not planning, that applies, and when an existing wall is upgraded, regulation 23 sets the standard it must meet under Part L.
Cost
Cavity, solid wall or both: pricing wall insulation
Measuring the wall is quick. Every window, door and floor edge is slow, so there is no price per metre.
What the wall is. If the borescope finds an empty, dry cavity, it can be filled from outside in a short visit. If the wall is solid, there is nothing to fill: it gets lined inside or wrapped outside, a bigger job with a bigger price. Nobody should quote before looking.
A wall that breathes. Older solid brick or stone lets moisture pass through. A vapour-tight board fixed to it can trap damp behind, so a breathable system such as wood fibre or insulating lime plaster may be right, and it costs more. The British Standard on moisture in buildings covers the risk.
Reach. Filling is drilled from outside, and a two storey wall behind shrubs or a lean-to needs a tower or scaffold, set under the rules on working at height. Lining from inside disrupts rooms, not the garden.
The junctions. Reveals round windows and doors, the edge of the floor, the eaves and a party wall are where heat slips out, and where condensation forms if the detailing is poor. That slow, fiddly work is most of the labour.
Ask any other installer whether they actually looked inside with a borescope, what system and thickness they specify, and who puts the plaster and decoration right afterwards.
If damp has appeared
Mould or damp after a wall was insulated
Damp patches or black mould on an outside wall after it has been insulated usually come back to two possible faults. Rain may be bridging the filled cavity, or warm indoor air may be hitting a cold spot at a junction.
On a solid wall lined with the wrong board, moisture can also be trapped behind the lining. Photograph the marks, note when they appear, and keep the room aired. We investigate before removing anything, because the cure depends on the cause. If the damp is spreading, ring us, as the form is slower, and if nobody answers, we ring back as soon as we are free. Wall insulation is booked Monday to Friday, 8am to 6pm.
Worth knowing
Opening the wall is the job, not the thing before the job
The hole is twelve millimetres, and that is the whole of it. It goes into a mortar joint rather than a brick face, the camera follows it in, the joint is made good behind us, and the business is over in the time it takes to drink a cup of tea.
Nothing about it is a preliminary. It is the only part of the survey that produces a fact, and every line of the quote afterwards is an inference drawn from what came back up that hole.
Which is also why a price arrived at without it is not a price for your wall. It is a price for an average wall, written in the hope that yours resembles one. And on a house of this age the honest answer is often the unprofitable one: the cavity is already evenly filled and dry, the wall is done, and the same money put into the loft, the draughts or the ventilation would do more for the house than anything we could sell you. Better said in your hallway than found out two winters later.
Who you are dealing with
Thomas Hannen, Bournemouth Roofing & Building Ltd, company 15471719
Walls in Holt, Holt Heath, Broom Hill and along the lanes to Furzehill, broadly BH21, are surveyed with Dorset Council as building control. Holt is an 8.6 mile run from our Boscombe base. The test hole is drilled, and the borescope read, by Thomas Hannen, whose company it is, and he prices the job.
Checkatrade shows a site-verified customer's 10 out of 10. Neither the survey nor the line-by-line written quote costs anything. The company is Bournemouth Roofing & Building Ltd, registered in England and Wales, company number 15471719. Before you book a visit in Holt, you can read our customers' Google reviews, word for word, on our reviews page.
Planning at a glance
Do you need planning permission in Holt?
Most repairs in Holt 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.
| Question | In Holt |
|---|---|
| Who decides | Dorset Council is the planning authority for Holt. Dorset Council's heritage pages set out what it controls. |
| Conservation area | None covers Holt, so a like-for-like repair is ordinary maintenance. |
| Listed buildings | Yes, there are listed buildings in and around Holt. If yours is one, work can need listed building consent. |
| Protected landscape | No National Park or National Landscape covers Holt. |
Questions
Questions about wall insulation in Holt
Can you tell what my wall is without drilling it?
The wall cannot be read reliably without drilling. Reveal depth and header bricks are worth checking and both are defeated by render, paint or a replacement frame, so a borescope through one small hole remains the only honest answer.
What does the check involve, and does it damage anything?
Twelve millimetres into a mortar joint, camera in, a look round, joint made good. Minutes rather than hours, and nothing visible left behind afterwards.
Can one house have two different kinds of wall?
Yes. One version is an older solid walled cottage with a cavity built extension on the back, and the two halves want completely different treatment from each other.
How long does the actual work take?
Pumping a cavity on an ordinary house with clear access is a day. Lining goes room by room instead, and each room runs to several days once making good and redecoration are counted in.
What if the answer is that I do not need anything?
Then you get told so on the visit. A cavity already filled evenly and dry is a wall that is finished, and your money will go further somewhere else in the house.
Nearby, and next door
Wall insulation near Holt
Nearby places we also cover for wall insulation, with straight-line distances from Holt, and the other trades we offer in Holt itself.
Wall insulation nearby
Our other trades in Holt
Wall insulation guides
Damp at the bottom of a wall: what it is PIR board vs mineral wool: which insulation? Hollow-sounding wall: blown plaster or dot and dabEverything we do in Ferndown Wall insulation, all areas Every area we cover
Free quote
Have the wall opened and read before you commit
Thomas comes out, drills one hole, shows you what is in the wall and prices the work in writing. The visit and the quote are free.