Spray Foam Insulation in Lewisville, TX

Lewisville took shape in layers. The dam that formed Lewisville Lake was finished in 1954, DFW Airport opened in 1974 and Vista Ridge Mall in 1989, and each one brought a new round of houses. In 2021 the city annexed Castle Hills and its roughly 18,000 residents. So a 1970s ranch house, a 1990s two-story and a townhome built after 2000 can sit a few miles apart here, and each needs a different plan.

Homes in Lewisville

In Lewisville Valley, near the lake, most homes went up between 1970 and 1980. They are mostly single-story ranch and minimal traditional houses of about 1,800 square feet with low hipped roofs, many with rear-entry garages, and as is common in North Texas, the ductwork runs through the attic. The rest of the city is newer. Most of Lewisville’s housing dates from the 1980s through the 2010s, and the median year is 1997. Fewer than half of all homes here are detached houses; most of the rest are townhomes, duplexes and apartments.

In the older houses, the job often starts with what is already up there. Unless someone has replaced it, the insulation on a 1970s attic floor is original, and after 45-plus years it may be packed down, stained or torn up by years of cable and HVAC work. If it is damaged or rodents have been in it, vacuum it out first; see insulation removal. Then the underside of the roof deck gets open cell foam. We recommend about 5.5 inches, which works out to roughly R-20, and it puts the ducts inside the conditioned space instead of in the 130°F air a July afternoon builds up there. See how an attic job runs on the attic spray foam page.

Castle Hills, Vista Ridge and two-story homes

Castle Hills has been building since the mid-1990s on the south side of SH 121, with Mediterranean villas, English storybook houses and townhomes on Lewisville addresses in ZIP code 75056. Vista Ridge, just west of I-35E about two miles north of Old Town, is mostly townhomes built after 2000.

In a two-story, the upstairs rooms take the heat first. The attic sits right on top of them, and the ducts that serve them run through it, so a game room or upstairs bedroom can run warmer than the rooms below. Foam on the roof deck holds the attic near indoor temperature, which is what those rooms need. Read about open cell foam, the type we use under roof decks.

If a bonus room sits over the garage, the garage matters as well, since a hot garage warms the floor of the room above it. See garage spray foam. Lewisville also has warehouse and office/warehouse space along SH 121, and we insulate that too; see commercial insulation.

Neighborhoods and ZIP codes we cover

In Lewisville we work in ZIP codes 75057, 75067 and 75077 and in Castle Hills (75056), including Old Town, Lewisville Valley, Vista Ridge and the neighborhoods along the lake, plus the small part of the city that sits in Dallas County.

Lewisville spray foam questions

My 1970s ranch house has a low roof. Is there room to spray the attic?

Usually. Spray foam goes on with a hose and gun, so the installer needs to reach the roof deck, not stand up at the edges. The tight spots are where a low hipped roof comes down to meet the walls, and those get a close look at the free measure. If deep old insulation is in the way, taking it out first gives room to work and a clear view of the deck.

I own a townhome in Vista Ridge. Can I insulate just my unit?

Usually, as long as your attic space is divided from your neighbor’s. At the free measure we check how the attic is separated and where your ducts and air handler sit. If your HOA maintains the roof, ask whether it wants to know about work under the roof deck before you schedule. Plan to stay out of your unit for about 24 hours after spraying.

We found mouse droppings in the attic insulation. What now?

That insulation should come out. Vacuuming it out before the foam goes on means you are not sealing old droppings and nesting material inside the house. After that, the roof deck gets open cell foam. Find and close the outside entry points too, because foam is insulation, not pest control.

Does spray foam make sense for an 1,800-square-foot ranch house?

Yes, if the ductwork runs through the attic. The reason to foam the roof deck is the same at any size: get the ducts out of 130°F air. A small house with a low-pitched roof also has less deck to spray. The price table on this page starts with the attic of a 1,500-square-foot house, a little smaller than the typical Lewisville Valley ranch.