Demilec Attic Insulation: The West Covina Owner’s Guide
We stock and install Demilec spray foam and Demilec-compatible attic insulation throughout West Covina, with most attic jobs running between $1,800 and $4,200 installed depending on square footage and foam type. Same-day and next-day appointments are available, and we answer the phone live around the clock. Most homeowners call us after noticing their upstairs rooms won’t hold temperature, their AC bill has climbed, or they’ve spotted gaps in existing foam that’s shrunk or pulled away from the rafters.
If your Demilec attic insulation isn’t doing its job anymore, here’s the straight answer on what it takes to fix it, what it costs in this part of the San Gabriel Valley, and whether you should touch it yourself. Walt Brenner and our crew have been working attics across West Covina since 2000, and we’ve pulled out our share of failed Demilec jobs installed by other contractors. We’re an independent service provider, not a Demilec dealer, which means we tell you the truth about what failed and what to put back.
Which Demilec Models This Applies To
Demilec’s attic products fall into two families: open-cell foam (Heatlok HFO and Sealection 500) and closed-cell foam (Heatlok HFO Pro and Heatlok Soy 200). In West Covina attics, most homes we see used open-cell on the roofline. The gotcha we run into constantly: Demilec changed the chemical formulation of Heatlok around 2016, so foam installed before that doesn’t always bond well when you try to patch it with the newer product. If your insulation predates that, plan on removal and reinstall rather than a patch job.
OEM Demilec parts like the spray gun tips, mixing chamber screens, and heated hose assemblies are solid, but we’ve found quality aftermarket equivalents from Graco and PMC perform identically for attic applications at a lower price. For West Covina homeowners, the honest answer is that the foam itself matters more than whose gun sprayed it. We run Demilec materials when the job calls for it, and we’ll tell you when a comparable Icynene or Johns Manville foam does the same thing for less money.
Signs Your Demilec Attic Insulation Is Failing
- Upstairs rooms run 8 to 12 degrees warmer than downstairs in summer. That’s the classic open-cell foam failure signal. Open-cell Demilec loses R-value when moisture gets in, and once the foam starts breaking down, the temperature gap between floors widens noticeably in West Covina’s July and August heat.
- You can see foam pulling away from rafters or sheathing. Demilec foam should be fully adhered. Gaps mean moisture intrusion or a bad chemical mix on install day. Either way, the insulation envelope is compromised and air is moving through the gaps.
- Your AC bill climbs year over year with no change in usage. In West Covina, where summer electric rates from SCE are punishing, failing attic insulation shows up on the bill first. A 20 to 30 percent jump usually means the attic is no longer holding the conditioned air.
- You smell a musty or chemical odor in the attic or upstairs hallway. This is a red flag. Either the foam was off-ratio when sprayed (leading to off-gassing that never fully cured) or moisture has gotten trapped. Either way, that foam needs to come out.
- Pest activity in the attic has picked up. Rodents burrow into open-cell foam easily. If you’re hearing scratching overhead at night, the foam has likely been compromised by nesting, and you’re losing insulation value where they’ve tunneled.
Replacement Cost & What’s Included
In West Covina, full attic insulation replacement with Demilec-compatible materials typically runs between $1,800 and $4,200 installed, with open-cell landing on the lower end and closed-cell on the higher end. Per-square-foot pricing for open-cell runs about $1.80 to $2.60, while closed-cell runs $2.80 to $3.80. Removal of failed Demilec foam adds $1.50 to $2.50 per square foot, which is why a bad install costs you twice: once to put it in wrong, once to get it out.
The specifics that move your price: attic square footage, roofline accessibility, whether we’re doing air sealing at the same time, and whether the existing foam needs full removal or can be partially remediated. Every quote we give in West Covina is line-itemed so you see exactly what you’re paying for. And every install, Demilec or otherwise, carries our Done Right Promise: lifetime workmanship, no fine print, no runaround. If it’s not done right, we come back and make it right.
DIY or Call Us?
You can safely check a few things yourself: look at the foam from the attic access hatch with a flashlight and check for obvious gaps or discoloration, write down the temperature difference between floors on a hot afternoon, and check your attic for pest droppings. That’s a useful starting point for the phone call. What you shouldn’t do is try to spray new Demilec foam or cut out old foam yourself.
Spray foam involves heated chemicals under pressure, and getting the mix ratio wrong means an attic full of uncured foam that off-gasses into your home. Removing failed Demilec foam requires respirators and containment because old foam can release particles. This is one of those jobs where the tool rental and PPE alone will eat most of what you’d save, and the risk isn’t worth it. Call us at (626) 612-1532 and we’ll come look. The estimate is free, and so is the second opinion if you already have a written bid from someone else.
FAQs
Properly installed Demilec open-cell and closed-cell foam should last 25 to 40 years in West Covina’s climate, but the local heat and occasional Santa Ana-driven moisture events mean real-world lifespan sits closer to 20 to 30 years before R-value degradation becomes measurable. If the foam was installed off-ratio or before the 2016 formulation change, failure can come in as little as 5 to 10 years. Call (626) 612-1532 and we’ll tell you what you actually have up there.
Small gaps and minor shrinkage can sometimes be spot-patched, but Demilec foam that’s pulling away in multiple areas, saturated with moisture, or tunneled by rodents almost always needs full removal and reinstall. Patching around the edges of a failing foam job buys you a year or two at most. We’ll give you an honest read on whether patch or replace makes sense for your West Covina attic.
Most West Covina attic insulation jobs take one day for removal and one day for reinstall, so plan on two days for a full replacement. Smaller patch jobs and partial remediations can often be completed in a single afternoon. We show up when we say we will, in uniform, and you’ll know who’s in your house.
We carry Demilec materials along with comparable foam from Icynene, Johns Manville, and Owens Corning on our trucks, plus Reflectix for radiant barrier applications, so there’s no waiting on a special order. If your existing attic setup needs something specific, we’ll tell you before we show up. Call (626) 612-1532 for a free estimate and we’ll get it scheduled.
Call Walt’s Insulation for Demilec Attic Work in West Covina
We’re the one down the road. Locally owned, owner-operated, and rooted in this community since 2000. Walt Brenner learned this trade at St. Philip’s College in San Antonio before heading west, and he’s been working attics across the San Gabriel Valley ever since. He keeps a thermos of bad coffee on the truck and says it’s the only thing that’s never let him down on a job site. Good insulation isn’t flashy. It just works, every day, whether you notice it or not. Our crew answers the phone live 24/7, and we offer $40 off any repair over $200, a free second opinion on any written estimate, no trip charge in our county, and 10 percent off for seniors and veterans, always.
Call (626) 612-1532 and tell us what your attic is doing. We’ll tell you what it needs and what it costs, straight up.
Written by Walt Brenner, Owner, Walt’s Insulation at Walt’s Insulation, serving West Covina and nearby areas.