Wall insulation in Milford on Sea
Half a mile from the water the first question is not what to put in the wall, it is whether the seaward elevation should be filled at all.
The site visit is free and so is the written itemised quote. Thomas Hannen prices every job himself.
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Most Milford on Sea houses built after the war have a cavity, older cottages are solid wall, and on a wall that takes the weather straight off the Solent, filling the cavity is not automatically the right answer. A cavity is there to stop water crossing from the outer leaf to the inner one, and on the most exposed elevations a full fill can give it a path. We check that wall before we quote it.
Milford on Sea walls give trouble on the south west side, after a fill, or in old cottages with no cavity. A house cold on the south west side and comfortable everywhere else. Damp patches or black mould on an outside wall a year or two after the cavity was filled. Or an older cottage with no cavity at all, where somebody has said the walls should be lined and nobody has said what that does to the building.
So the visit starts with what the wall actually is. We drill one small hole, put a borescope in and look: is there a cavity, how wide, is it clear, is it dry, and has anything in it slumped. Then you get a written itemised quote with the survey, the system, the junctions and the ventilation on separate lines. Both are free, and if the answer is that this wall should be left alone we will say so. For the loft too, see insulation in Milford on Sea.
The work
Filling a cavity, lining a solid wall, and knowing which is which

The borescope check, before anything else. One hole, a camera, and a straight answer. A clear dry cavity of a sensible width can take a fill. One bridged by mortar snots, one already wet, one too narrow, or one on a wall rated severely exposed for wind driven rain under BS 8104 cannot, or not with every material. Nobody can tell you that from the pavement, and no honest quote is written without it.
Cavity fill: bead or mineral wool. In Milford on Sea, bonded polystyrene bead is blown through a pattern of drilled holes and sets into a mass that will not settle. Blown mineral wool is water repellent and cheaper, but it is the one we would not put in an exposed seaward wall, because it can carry water across a wet cavity. Either way the holes are made good in a matched mortar, and a house is a day.
Solid walls, which cannot be filled at all. A nine inch brick wall in Milford on Sea, a rendered cob or flint one, or anything built before the brick and block cavity became standard has nothing to fill. The two real options are internal wall insulation or external wall insulation, and they are different jobs at different prices.
Internal wall insulation. Insulated plasterboard bonded and mechanically fixed to a flat Milford on Sea wall, or PIR board such as Celotex or Kingspan set between battens or a stud, then boarded and skimmed. It eats a little room and it moves radiators, sockets and skirtings. On a breathable wall it stays breathable, in wood fibre and lime, never a vapour tight sandwich.
External wall insulation. Board fixed to the outside, a render carrier and mesh over it, then a through coloured finish. On a Milford on Sea house it keeps the wall itself warm, so interstitial condensation has nowhere to form, and it takes no floor area. It changes the look of the building completely.
The junctions, which are most of the labour. Window and door reveals, the threshold, the floor junction, the eaves and the joist ends. A Milford on Sea reveal too shallow for a normal board takes a thin aerogel panel instead. Get these wrong and you have built a cold bridge, and a thermal bridge is where the dew point lands and where black mould turns up first.
Failed and slumped fill. Where a fill has settled and left the top of the wall bare, or has wetted up, it is extracted through drilled holes and the cavity dried first.
Ventilation, because a tighter house needs it. Trickle vents in the windows, a working extract in the kitchen and bathroom, and air bricks left clear. Approved Document F sets what is expected, and airtightness without ventilation is how you turn a draughty house into a damp one.
How it runs
Insulating walls that take the driven rain

Before pricing, Thomas drills a single small hole and looks into the wall with a borescope to see whether there is a cavity and what is already in it. He writes the quote himself, and any fill is put in by a registered installer with a CIGA certificate. It shows the inspection, the insulation chosen and its thickness, the work around window and door reveals, ventilation, and disposal.
If a Milford on Sea cavity is clear and dry and the wall not badly exposed, it is filled from outside and the holes pointed to match. If the wall is solid, or the cavity is wrong for fill, the inside face is lined with insulated plasterboard or a stud frame with mineral wool, then skimmed. We go room by room, sheeting floors and keeping dust contained. Damp or a fault uncovered in the wall is photographed and priced, and we go on only when you agree.
Planning here is New Forest District Council. An internal lining needs no permission, as the Planning Portal's insulation guidance confirms. External wall insulation changes the outer face, so the external walls guidance applies, and for a house within the conservation area in central Milford it needs planning permission. A listed building needs consent even for internal work. Building control comes in under regulation 23 once a thermal element is renovated, and Part L sets the U-value.
Cost
Cavity, exposure and junctions on a coastal wall
The flat middle of a wall is quick to insulate. The price is set at its edges, and by the weather.
Which wall. A clear, dry cavity can be filled in a short visit. A solid wall has to be lined inside or insulated outside, which costs more. The borescope decides it.
Exposure. This near the sea, with the most exposed face turned south west, driven rain can cross a filled cavity and bring damp through to the plaster. BS 8104 is how that exposure is assessed, and on the worst walls a lining or external insulation is the safer route.
Junctions. Window and door reveals, the floor junction and the eaves are where heat leaks and condensation forms. That detailed work is slow and makes up most of the labour.
Access. Cavity fill on a bungalow comes off a ladder or tower. A two storey seventies house needs more, and the work at height rules decide the platform. On a block of flats the managing agent has to agree first.
Ask anyone quoting: has the wall been checked with a borescope? What system and thickness? How are the reveals and floor junctions finished?
If damp has appeared
Damp patches on a wall that was insulated
Phone rather than use the form. Damp or black mould on an outside wall after cavity fill or lining usually means water is crossing the cavity, or warm air is meeting a cold spot at a junction. We look before taking anything out, because the fix depends on the cause.
Send a photo and say which elevation it is on; on a seaward wall that often answers the question. Wall jobs are scheduled Monday to Friday, 8am to 6pm. If we miss you, we will call back as soon as we are able.
Worth knowing
Why a seaward cavity is treated differently
Wind driven rain is not the same as rain. It arrives horizontally with enough force to be pushed into the face of a wall and held there, and the exposure maps in BS 8104 put this coast in the severe band. Salt matters too, because it keeps masonry damp for longer between showers, so an outer leaf here dries more slowly than the same brick ten miles inland.
That changes one decision. An unfilled cavity is a break. Water gets through the outer leaf, runs down the inside face of it and goes out again at the trays and weep holes without ever touching the inner leaf. Put the wrong fill in, or any fill into a cavity bridged with mortar droppings, and you have handed that water a bridge. The damp that follows is penetrating rather than condensation, and it shows on the inside of the elevation the weather comes from.
So we treat the seaward and south west walls of a Milford house separately from the sheltered ones. Sometimes the answer is a bead fill, which bonds and does not wick. Sometimes it is filling three walls, leaving the fourth and lining that one inside. Sometimes, on a rendered wall already showing cracking or a blown patch, it is to sort the render out first.
Who you are dealing with
Who insulates your walls
We are 10.3 miles from Milford on Sea, in Boscombe, and also insulate walls in Keyhaven, Hordle and the lanes towards Barton, all SO41 under New Forest District Council. The work is carried out by Bournemouth Roofing & Building Ltd, registered in England and Wales, company number 15471719. Before you book a visit in Milford on Sea, you can read our customers' Google reviews, word for word, on our reviews page.
Thomas Hannen, who owns it, does the borescope check and the pricing himself. A verified customer scored us 10 out of 10 on Checkatrade. You will not pay for the visit, or for the itemised written quote that follows it.
Planning at a glance
Do you need planning permission in Milford on Sea?
Most repairs in Milford on Sea 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 Milford on Sea |
|---|---|
| Who decides | New Forest District Council is the planning authority for Milford on Sea. The National Park boundary runs close by, and the Park's property map shows which side an address falls. |
| Conservation area | Yes: Milford-on-Sea Conservation Area. Check whether your street is inside the boundary before changing anything visible. |
| Listed buildings | Yes, there are listed buildings in and around Milford on Sea. If yours is one, work can need listed building consent. |
| Protected landscape | No National Park or National Landscape covers Milford on Sea. |
Questions
Questions about wall insulation in Milford on Sea
Should I fill the cavity on a wall facing the sea?
Not without the borescope check first, and sometimes not at all. On a severely exposed elevation with a porous outer leaf we would rather fill the sheltered walls and line that one internally.
How do I know whether I even have a cavity?
A nine inch solid wall and a brick and block cavity wall look similar from outside. One drilled hole and a camera settle it in a few minutes, and that is part of the free visit.
Damp appeared after our cavity was filled. Can it be taken out?
Yes, through drilled holes, and the cavity is then left to dry. We look first, because if the water is coming through cracked render or a failed sill the fill may not be the cause.
How many days should I allow for the work?
A straightforward cavity fill is usually one day. Internal wall insulation is worked room by room and runs to days, because the reveals and the making good take the time.
Will insulating the walls change my EPC?
It normally does, and heat loss through the walls is a large share of the total, so the payback is real. We will not put a figure on it, because it turns on how you heat the house.
Nearby, and next door
Wall insulation near Milford on Sea
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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 Lymington Wall insulation, all areas Every area we cover
Free quote
Find out what your walls actually are
Thomas comes out, checks the cavity with a borescope and prices the wall, the junctions and the ventilation in writing. The visit and the quote are free.
