Northline Insulation Co. · Wrenfield & the Loring Valley · Est. 2011
The heating bill is the brochure. We would rather show you the meter.
Northline audits, air-seals and insulates houses around Wrenfield — a blower-door reading before we quote, another before we leave, and cellulose in between. Every figure on this page came off a finished house in the valley, not a manufacturer's pamphlet.
Services & rates
The rate card
Prices from last quarter's finished jobs in Wrenfield and the valley. The audit is the entry point: it finds the leaks, prices the fix, and its $195 comes off the invoice the moment you book. Every line already includes patching, clean-up and both blower-door readings.
Attic top-up$2.40–3.10 / sq ft
Cellulose blown over what is there to a settled R-60, dams and baffles set first
Air sealingfrom $890
Top plates, wire and pipe penetrations, chases — sealed before any insulation goes in, verified by blower door
Dense-pack walls$4.75 / sq ft of wall
Cellulose at 3.5 lb/ft³ through 2-inch holes, plugged and patched the same day
Rim-joist seal$11.50 / lin ft
Two-part foam on the box sill, basement side, with the sill plate sealed to the stone
Crawlspace ceiling$3.85 / sq ft
R-38 dense pack under the floor with a ground-vapor management plan
Blower-door audit$195
CFM50 before and after, infrared scan, written scope — the fee is credited to any work we then do
Services
The method, in order
01
The audit — $195, credited to the job
We depressurize the house with a blower door and walk the rooms with an infrared camera in January air. You watch the walls stream purple where the heat is leaving. The scope is written on the spot, room by room, leak by leak.
02
Air seal — from $890
Two-thirds of the savings in an old house come from holes, not from thickness. Top plates, balloon-frame chases, the gap around the chimney, the basement ceiling — sealed with foam and caulk before a single bag of cellulose comes off the van.
03
Dense-pack the walls — $4.75 / sq ft
Empty wall cavities filled through a 2-inch hole per bay, blown to 3.5 lb/ft³ so the cellulose will not settle, then plugged, patched and photographed for your file. Most houses lose the hollow-drill sound in a day.
04
Blow the attic and test out
R-60 over dams at every recessed light and hatch, baffles keeping the soffits breathing, then the blower door comes back out. The test-out reading goes beside the first one on your invoice — the job is not done until the number moves.
Why the meter
A number we are willing to guarantee
We quote the CFM50 reduction we expect — a percentage, in writing, on the scope. Old houses in the valley test anywhere from 3,000 to 5,500 CFM50 before we touch them; the audit tells us which end of that your house is on and what sixty percent of it looks like. The meter either agrees with us or it does not, and you get to watch.
The test-out promise
If the second blower-door reading does not beat the percentage on the scope, we come back and finish the sealing at no charge — and re-test until it does. The readings are printed on the invoice, both of them.
The valley says
Meters, read twice
Our 1974 ranch tested 4,100 CFM50 at the audit. Northline sealed it, dense-packed the walls and blew the attic, and the test-out read 1,600. February's gas bill came in at $214 against $327 the year before — same thermostat, same family.
Three winters of ice dams on the north slope, two roofers, one insurance claim. Northline found the heat leaking through the top plates with the camera, sealed and re-blew to R-60, and the dams have not come back in two years. Should have been the first call.
They dense-packed our hollow-tile walls in a single day and you cannot find the holes — I looked with a ladder. The downstairs went from the room we avoided in January to the one the dog claims.
Before the audit
Straight answers
The five we get on every first call. If yours is not here, the shop line at the bottom of the page runs seven to five, valley-wide.
What is the payback on all this?
On the average valley house we have measured — 31% off the heating bill — the work pays for itself in three to five heating seasons, and the utility rebate programs we file for you usually pull a season off that. The audit tells you your house's number before you commit to anything.
Is dense-pack messy?
One 2-inch hole per wall bay, drilled inside with a dust skirt, plugged with foam plugs and patched flush the same day. The cellulose stays in the wall — that is the point of the 3.5 lb/ft³ density. We drop cloths everything and the van carries its own HEPA vacuum.
Code says R-49. Why blow to R-60?
Because the marginal cost of the extra four inches is a bag count, not a second job, and at R-49 the attic is still where a quarter of your heat goes. On small or already-half-full attics we will quote both and let the audit decide.
Can a house be sealed too tight?
Yes, and we check for it. Combustion appliances get a worst-case spillage test after sealing, and if the house needs make-up air we spec it in the scope. Tight and dumb is a defect; tight and ventilated right is what a new build is.
Do you handle the rebates?
We file the paperwork for every utility and state program the work qualifies for and take the rebate off the top of the invoice where the program allows. The audit report is written in the format the programs ask for, because we write it that way on purpose.
Audit season opens in September — valley-wide, usually within the week. (555) 018-4429 · audits@northlineinsulation.example
Get your before-and-after
Tell us the town, the decade the house was built and what January feels like upstairs. The audit is $195, credited to any work you book, and both CFM50 readings end up printed on the invoice. audits@northlineinsulation.example