Redframe Home Performance · Blower-door diagnostics & air sealing · Milford Narrows, the Wealdmoor flats & the Narrows parishes · By appointment
The blower door does not care what the invoice said.
Redframe depressurises the house and reads the truth: every leak found in infrared, every fix priced off the reading, and a re-test that either hits the number the contract names or we keep working for free. Insulation is the second half of the job — the first half is air, and R-values on an unsealed house are a rumour with a receipt.
Every job ends at a number · CFM50 before and after, printed · infrared plates in every binder · air sealing first, fibre second, always in that order
Diagnostics & fixes
The flat card
Prices like the poster above: flat where the day is fixed, per-foot where the house decides, and nothing on the card that the door or the camera cannot verify. The diagnostic day is the whole sales process — readings first, quotes second, always in that order.
The diagnostic day$480 flat
Blower door, infrared plates, smoke pencil — the readings are yours whatever you build
Air sealingfrom $1,450
Per 1,000 sq ft of house — top plates, rim joist, the holes the plates named
Dense-pack cellulose wallsfrom $3.10 / sq ft
Per sq ft of wall, density gauged to 3.2 lb/ft³ and printed
Attic to R-60from $2.40 / sq ft
Per sq ft over the flat — sealed first, dressed clearances
HRV fitted & balancedfrom $3,900
Commissioned with the airflow report stapled in
The re-testincluded
Same fan, same gauge, same door — target named in the contract
The premise
Diagnose before you insulate
A house is not cold; it is leaky, under-insulated, or both in that order — and the order matters, because fibre over a hole is a duvet over an open window. The diagnostic day reads which it is with instruments instead of habits: the fan measures the hole, the camera finds it, and the card prices fixing it. Some houses need only the first day, and we say so and leave.
The re-test clause
Your contract names the CFM50 the finished house will read. The re-test is included and the target is contractual: miss it and Redframe returns — sealing, re-testing, returning — until the gauge agrees, on our calendar and our invoice, not yours.
How it runs
The four beats, every job
No choreography — just the order the physics insists on, the same on a Narrows cottage and a Wealdmoor dairy alike.
Depressurise
The red frame goes in the front door and pulls the house to minus 50 pascals — every leak in the building starts whistling to the fan.
Photograph
The infrared camera walks every room under suction; the plates show the cold plumes at wire, flue, hatch and rim joist, printed by supper.
Seal
Foam, gasket and smoke pencil down the list the plates named — the running CFM count drops all afternoon, and the binder keeps score.
Re-test
Same fan, same gauge: the after-number against the contract’s target. Over it and we shake hands; under it and we come back.
2025 — 2026
Plates from the book
Six pages from last season’s binders — the infrared plates that found the work and the door numbers that proved it. The book itself runs to eleven volumes and lives at the Narrows shop.
The infrared argument
What the camera says that the eye cannot
Every plate in the book is a fact about a house that nobody living in it could have named: the cold plume off a top plate, the wind washing through a rim joist, the cathedral bay the builders forgot. We print them because a fact photographed is a fact priced — and a fact priced is a fact fixed.
The plates found the cold river over the front door — a void behind the lintel the builders left in 1968. Two cans of foam and forty CFM50. Nobody sells you that fix; an instrument hands it to you.
Fair questions
The five the fan hears
The five the front door hears while it holds the frame — which is every house’s way of saying the same five things. The shop line answers the rest, seven to five, Narrows time.
Why air sealing before insulation — isn’t fibre the point?
Fibre slows conduction; it does almost nothing for the holes where wind moves through the building, and the fan has the receipts: on the median Narrows house, half the measured leakage is attic-floor bypasses sitting under — and defeating — perfectly good insulation. Seal first and the R-value you already own starts working; pack after and the new R-value works too. The card prices them in that order because the physics does.
What do the numbers CFM50 and ACH50 actually mean?
Cubic feet per minute of air pulled through the house at a fifty-pascal suction, and the same expressed as house-volume air changes per hour. They are the building’s honest leakage score — one number, one fan, comparable across every house ever tested, which is why the contract names the target as CFM50 and why the re-test reads the same gauge.
How tight is too tight for a house to breathe?
Houses should be ventilated on purpose, not by accident — a leak is not a lung. Where the test-out lands tight of healthy, the card carries the HRV: balanced, commissioned, recovering the heat from the stale air it exchanges. Every Redframe scope computes the ventilation line before anyone drills, so the answer arrives with the quote instead of after the invoice.
Can you check the insulation another crew installed?
That is the diagnostic day’s best trick: the camera reads the voids and the slump through the finish, the door reads the leaks the fibres never addressed, and the plates go in your binder whether or not you hire us to fix what they show. Eleven scopes last year ended with "the insulation is fine; the sealing is the bill" — which cost their owners a diagnostic day and saved them four figures.
What if the re-test misses the target?
Then the clause earns its keep: we return, seal what the plates name next, and re-test — again and again, on our calendar and our invoice, until the gauge reads the contract’s number. It has taken three visits exactly once in nine years, a stone wall with a cellar behind it, and the binder keeps the whole story on the shelf.
Three insulation outfits quoted me walls I already had. Redframe put a fan in my front door, showed me the cold river over the lintel and the wind through the rim joist on camera, and priced the fixes off the readings — the whole sealing job cost less than the cheapest fibre quote and cut the leakage by more than half. The re-test read 40 CFM50 inside the target with my own kettle running. I have sent them six neighbours and they have sent me six thank-you cards.
The book, in figures
Nine seasons, same fan
Diagnostic days $480 flat, readings yours either way · (555) 027-6620 · readings@redframe.example
Book the fan for a day
The diagnostic day is the whole intake: the frame in your front door, the camera through your rooms, and the readings in a binder with your name on it before anyone quotes. Fix what the plates name or take them to whoever you like — they were facts before they were ours. readings@redframe.example