Attic feels well over outdoor temperature in summer

Poor ventilation shortens shingle life and raises cooling cost at the same time. Check for a ridge vent and clear soffit intake before spending anything on the roof surface.

Quick answerAn attic that feels far hotter than outdoors on a summer afternoon usually isn’t moving enough air. Poor ventilation shortens shingle life measurably and raises cooling cost at the same time. Check for a ridge vent or other exhaust near the top and clear soffit intake at the bottom before spending anything on the roof surface itself. You can check this yourself, no call needed.

An attic needs air coming in low and going out high. Exhaust without intake, or intake blocked by insulation, leaves heat trapped right under the shingles.

Wooden beams and ceiling in an attic — Attic framing. Air should come in low at the soffits and leave high at the ridge. Photo by C on Unsplash.

This is most common in homes built roughly 1980 to 2000. The polybutylene and aluminum-wiring window, 150 amp panels, R-22 systems and first-cycle architectural shingle.

1Why attics overheat

Problem	What happens
No exhaust high up	Hot air collects at the peak with nowhere to go
No soffit intake	Exhaust vents have no fresh air to pull in, so they barely work
Insulation blocking soffits	Vents exist outside, but insulation stuffed into the eaves blocks the airflow
Mixed exhaust types	Different vent types near each other can pull air from each other instead of from the soffits

2How to check it yourself

Look at the ridge from the groundA ridge vent shows as a low, continuous cap along the peak. Also note box vents, turbines or gable vents.
Look under the eavesCheck the soffits for vents. Solid soffit boards with no openings mean no intake.
Look from inside the atticOn a sunny day you should see light at the eaves. If insulation is packed tight against the roof deck there, intake is blocked.
Check for moistureIn winter, frost or damp on the underside of the deck is another sign of poor airflow.

Attic safety in summer

A summer attic can be dangerously hot. Go up early in the morning, bring water and a light, and step only on joists or boards. Stepping between joists can put a foot through the ceiling.

3Fixing it

Do it yourself

Clear insulation away from soffit vents
Install baffles at the eaves so insulation can’t block the air path
Clean painted-over or clogged soffit vents
Seal gaps that let house air leak into the attic

Hire a pro

Cutting in a ridge vent or new soffit intake
Removing mixed or competing exhaust vents
Ventilation is being redone as part of a reroof

How much vent area you need depends on the attic size and local code. Check local code, or ask the roofer to show the intake and exhaust numbers in writing if the work is part of a reroof.

4What drives the cost

Clearing soffits and adding baffles is mostly your time. Cutting in new ridge or soffit vents costs more and is cheapest during a reroof. See roofing cost.

5Questions

Will an attic fan fix it?

Only if there’s enough intake. Without it, a fan can pull conditioned air up from the house instead.

Do I have a ventilation problem if I have a ridge vent?

Possibly. A ridge vent needs soffit intake to work. See ridge vent installed but soffit baffles missing.

Does a hot attic void my shingle warranty?

Many shingle warranties require proper ventilation. Read yours to see what it says.

Written by Jaylan Jones. I Like To Exterior Services earns a referral fee when a call connects to a contractor. See our business-model disclosure.