What is a radiant barrier, and does it work in Texas?
What the foil does, how much it can help, and how it fits with attic insulation.
Home / Attic Insulation & Venting
Attic insulation & venting · Dallas–Fort WorthThe fastest way to a more comfortable house.
On a Texas summer afternoon your attic can be the hottest space you own. Without enough insulation on the attic floor, that heat pushes into the rooms below for hours. Sealing the gaps, topping up the insulation and making sure the attic can vent its heat is usually the most cost-effective comfort upgrade we offer.
Attic insulation & venting
Two attic systems that work together.
Insulation and air sealing stop attic heat from reaching your rooms. Venting moves that heat and moisture out of the attic. We check and plan both at every assessment.
Insulation & air sealing
Attic insulation
We seal the gaps first, then blow in insulation to the depth our climate calls for.
- Air sealing at top plates, can lights and attic penetrations
- Blown-in insulation brought up to about R-49, ENERGY STAR's recommendation for our zone
- Baffles that keep soffit vents open
- Usually done in about a day
See attic insulation →
Attic ventilation
Venting & solar attic fans
Balanced airflow lets trapped heat and humidity escape, with a solar fan where the attic needs more help.
- Intake at the soffits, exhaust near the ridge
- Remington Solar 40 Watt solar attic fans; we're an authorized dealer
- Each fan covers about 1,800–2,400 sq ft of attic
- Limited lifetime warranty on parts
See attic venting →
R‑49
ENERGY STAR recommends R-49 for an uninsulated attic in our climate zone, or adding about R-38 if you already have 3–4 inches. That's well over a foot of blown-in insulation. We'll measure what you have today and show you the gap.
Source: ENERGY STAR, recommended home insulation R-values (climate zone 3)
What we do
Air seal first. Then blow in the insulation.
Insulation slows heat, but it doesn't stop air. Hot attic air leaking down through gaps around lights, wiring and the attic hatch can undo a lot of the benefit, so we seal those first.
Inspect and measure
We check the depth and condition of your current insulation, ventilation, and any signs of moisture or damage.
Air seal
We seal the gaps between your living space and the attic: top plates, wiring and plumbing holes, light fixtures, and the attic hatch.
Protect ventilation
Baffles at the eaves keep new insulation from blocking the airflow your roof needs.
Blow in to the target level
Insulation goes in evenly to the recommended depth, with depth markers so you can see what you paid for.
Does any of this sound familiar?
Signs your attic needs more insulation.
Upstairs is much hotter
If the bedrooms upstairs are several degrees warmer than downstairs all summer, the attic is the first place to look.
You can see the joists
If the top of your insulation is level with or below the ceiling joists, there isn't much there.
The AC never stops
On summer afternoons the system runs constantly and still can't keep up.
Ceilings feel warm
Put your hand on an upstairs ceiling at 5 p.m. in July. It shouldn't feel warm.
Depth guide
How deep is R-49?
R-value measures how well insulation resists heat. Blown cellulose packs more R-value into each inch than blown fiberglass, so the same target takes less depth.
| TARGET | BLOWN FIBERGLASS | BLOWN CELLULOSE | WHEN IT APPLIES IN DFW |
|---|---|---|---|
| R-30 | about 11–14 in | about 8–10 in | A common level in older homes; below today's recommendation for our climate |
| R-38 | about 14–17 in | about 10–12 in | How much ENERGY STAR suggests adding if you already have 3–4 inches |
| R-49 | about 18–22 in | about 13–15 in | ENERGY STAR's recommendation for an uninsulated attic in climate zone 3 |
Depths use about R-2.2 to R-2.7 per inch for blown fiberglass and R-3.2 to R-3.8 per inch for blown cellulose. Exact depth depends on the product; we follow the manufacturer's coverage chart and install depth markers. Sources: ENERGY STAR, U.S. DOE Building America Solution Center. More in how much attic insulation a DFW home needs.
Air sealing
Where attic air leaks hide.
Most of the leaks between your living space and the attic are hidden under the old insulation. These are the spots we seal before anything is blown in.
The attic hatch or pull-down stairs
Often an unsealed, uninsulated panel. We weatherstrip it and insulate the lid or add an insulated cover.
Recessed lights and fixtures
Holes around can lights and ceiling boxes pull hot attic air into rooms. Fixtures rated for contact with insulation can be sealed; others need a proper cover.
Top plates
The tops of interior walls are open to the attic in many homes. Sealing the gaps along them stops air moving through the wall cavities.
Wiring and plumbing holes
Every pipe, vent stack and wire that passes through the ceiling leaves a gap. We seal them with foam or caulk.
Chimney and flue chases
Openings around flues need fire-rated materials and the right clearance, never ordinary foam.
Dropped soffits and duct chases
Framed boxes above cabinets and around ducts are often open to the attic on top. We cap and seal them.
Source: ENERGY STAR, why seal and insulate.
Materials
Fiberglass or cellulose?
Both are proven blown-in insulations for a vented DFW attic. We recommend one based on your attic, and either one goes in over a sealed attic floor.
| MATERIAL | WHAT IT IS | R-VALUE PER INCH | GOOD TO KNOW | BEST FOR |
|---|---|---|---|---|
| Blown fiberglass | Loose glass fibers, often with recycled glass content | About R-2.2 to R-2.7 | Lightweight; doesn't absorb moisture; needs more depth for the same R-value | Most attics, especially with ample height |
| Blown cellulose | Recycled paper fibers treated for fire and pest resistance | About R-3.2 to R-3.8 | Denser, so it fills around obstructions well; settles somewhat, so it's installed a little deeper | Attics with tight clearances or lots of framing |
| Spray foam (roof deck) | Foam sprayed on the underside of the roof | About R-3.6 (open cell) to R-6 (closed cell) | Seals and insulates in one step, at a much higher cost | Attics with HVAC and ducts that are hard to seal from the floor |
Compare in detail: spray foam vs. blown-in insulation.
Attic venting
Let the attic breathe.
Insulation slows heat on its way down. Venting moves hot, damp air out of the attic in the first place. The two work together, so we check both at every assessment.
Intake at the eaves
Soffit vents low on the roof let cooler outside air into the attic. Blocked or painted-over soffits are one of the most common problems we find, and baffles keep new insulation from covering them.
Exhaust up high
Ridge vents or roof vents near the peak let rising hot air escape. Without an exit, heat builds up under the roof deck all afternoon.
Balanced airflow
Intake and exhaust need to be in balance so air flows across the whole attic, not in short circuits. A balanced attic runs cooler and stays drier, which helps protect the roof deck and shingles.
Solar attic fan · Authorized Remington Solar dealer
40 Watt Solar Attic Fan, Builder Series
Genview is an authorized dealer for Remington Solar attic fans. The 40 Watt Builder Series is a steel-built, solar-powered roof fan that pulls hot, humid air out of the attic on its own. A built-in thermostat and humidistat switch it on when the attic gets hot or damp, and the included 110V hybrid adapter keeps it running at night and on cloudy days.
- 2,400 sq ftAttic coverage
- 1,500+ CFMAirflow (manufacturer rating)
- 80°F / 75% RHTurns on at
- LifetimeLimited parts warranty
Why we install it
- Runs on sunlight, so it moves attic air without adding to your electric bill during the day
- The 110V hybrid adapter switches it to house power at night and in low light
- Built-in thermostat and humidistat: on at 80°F or 75% humidity, off below 65°F and 55% humidity
- Quiet brushless DC motor for long life
- High-performance steel housing with a powder-coated finish
- Seamless flashing and shroud for a weather-tight roof install
- Stainless steel animal screen and hardware
- Tilt panel to catch the most sun on any roof slope
- Texas Windstorm Certified
Installed on real roofs
Remington Solar attic fans on shingle and metal roofs. Photos: Remington Solar.
Regular attic fan vs. our solar attic fan
| REGULAR ELECTRIC ATTIC FAN | 40 Watt | |
|---|---|---|
| Power | Wired to house electricity; typical models draw about 250–300 watts while running | 40 watt solar panel, plus a 110V hybrid adapter for nights and cloudy days |
| Running cost | Adds to your electric bill every hour it runs. A Florida Solar Energy Center review found that draw is often greater than the cooling energy it saves | Uses no grid power in daylight; draws house power only through the hybrid adapter at night or in low light |
| Installation | Needs a dedicated electrical connection, often by an electrician | Solar powers it directly; the hybrid adapter connects to 110V power through a surge protector |
| Controls | Usually a thermostat; humidity control varies by model | Thermostat and humidistat built in: on at 80°F or 75% humidity |
| Noise | Conventional motors are often noticeable from inside | Quiet brushless DC motor |
| Build | Varies by brand | Powder-coated steel, stainless screen and hardware, Texas Windstorm Certified |
| Warranty | Varies by brand | Limited lifetime warranty on parts |
| Needs to work well | Either way: clear soffit intake and an air-sealed ceiling, so the fan pulls in outside air, not cooled air from the house. We check both at your assessment. | |
Source: Florida Solar Energy Center, Performance Assessment of Photovoltaic Attic Ventilator Fans (2000), which notes conventional attic ventilators often draw 250–300 W. Remington Solar specifications.
Specifications
- Model
- Remington Solar 40 Watt Solar Attic Fan, Builder Series
- Coverage
- Attics up to 2,400 sq ft (more fans can be combined for larger attics)
- Airflow
- Over 1,500 CFM (manufacturer rating)
- Power
- 40 watt solar panel, plus a 110V hybrid adapter for nights and cloudy days
- Controls
- Thermostat and humidistat: on at 80°F or 75% RH, off below 65°F and 55% RH
- Motor
- Brushless DC
- Construction
- High-performance steel, powder coated; seamless flashing and shroud; stainless steel screen and hardware
- Color
- Black
- Weight
- 31 lb
- Certification
- Texas Windstorm Certified
- Warranty
- Limited lifetime warranty on parts from Remington Solar
- Dealer
- Genview is an authorized Remington Solar dealer
The 110V adapter must be connected through a surge protector; a power surge or lightning strike can damage it and void its warranty coverage.
Beyond insulation
Other ways to take heat out of the attic.
Insulation and air sealing come first. These can add to the result, depending on your home.
Radiant barriers
Reflective foil that reflects the sun's heat back toward the roof. Most useful when ducts run through the attic. Does a radiant barrier work in Texas?
Duct sealing
Leaky attic ducts can lose cooled air before it reaches upstairs rooms. ENERGY STAR notes ducts commonly lose 20–30% of the air they carry. Why the upstairs runs hot
Windows and doors
Once the attic is handled, sunny windows and drafty doors are the next places heat gets in. See how the whole house works together
Questions
Attic insulation & venting FAQ
Why solar instead of a regular electric attic fan?
A regular powered attic fan typically draws 250 to 300 watts whenever it runs, and research from the Florida Solar Energy Center found that draw is often greater than the cooling energy it saves. A solar attic fan runs on its own panel in daylight, so it isn't adding to your bill while it works. Compare them.
What solar attic fan do you install?
The Remington Solar 40 Watt Builder Series. Genview is an authorized Remington Solar dealer. It covers attics up to 2,400 square feet, runs on solar power with a 110V hybrid adapter for nights and cloudy days, and switches on automatically when the attic is hot or humid. See the specifications.
Will a solar attic fan work with my existing vents?
It needs intake to work well, usually soffit vents low on the roof, so it can pull fresh air in as it pushes hot air out. We check your intake and exhaust at the assessment and place the fan so it helps, rather than pulling conditioned air up from the house.
Does my attic need more ventilation?
It depends on the roof. Signs of poor venting include an attic that stays very hot into the evening, moisture on the underside of the roof deck, and blocked soffit vents. We check intake and exhaust at your assessment and tell you whether anything needs to change.
How long does the job take?
Most homes are sealed and insulated in a single day.
Do you remove my old insulation?
Usually not. New insulation goes on top. If the old material is wet, moldy or contaminated, we'll tell you and quote removal separately.
Fiberglass or cellulose?
Both work well blown in. We'll recommend one based on your attic and explain why. See how they compare.
Do I need to be home?
Someone needs to let the crew in and be available during the job. We don't need to enter most rooms beyond the attic access.
How much attic insulation does a DFW home need?
ENERGY STAR recommends about R-49 for an uninsulated attic in North Texas (climate zone 3), which is well over a foot of blown-in insulation. If you already have 3 to 4 inches, the recommendation is to add about R-38. Read how much attic insulation a DFW home needs.
How much does attic insulation cost?
A typical blown-in top-up in DFW often costs in the low thousands of dollars. Larger attics, air sealing, removing old insulation and spray foam can push it higher. We measure your attic and give you a written price. See attic insulation cost in DFW.
Is spray foam better than blown-in insulation?
Not for most homes. For a standard vented attic, air sealing plus blown-in insulation gives the best comfort for the money. Spray foam costs more and makes the most sense when ductwork and HVAC sit in a hard-to-seal attic. Compare spray foam vs. blown-in.
Should I add a radiant barrier?
A radiant barrier can help in a hot, sunny climate, especially when ducts run through the attic, but it supplements insulation rather than replacing it. The U.S. Department of Energy cites cooling savings of about 5% to 10% in some studies. Read does a radiant barrier work in Texas?
Why is my upstairs so much hotter than downstairs?
Usually the attic, the ducts and the sun: the upstairs sits under a hot attic, gets its cooling through attic ductwork and takes the most direct sun. Sealing and insulating the attic is usually the first fix. See why the upstairs runs hot.
Don't see your question? Call 469.340.4780 or book a free home assessment.
From the blog
More on attic insulation
Find out how much insulation your attic really has.
We'll measure it during your free assessment.