attic insulation and cooling improvement tips

Not that I support it or am against it (slightly against since it can turn a home into a Faraday cage)...but what do people in La think about radiant barriers installed in your attic to reflect the radiant heat energy? Are they used much?

Reason I don't like them is because I'm a ham radio operator and my antenna is in my attic and radiant barrier block my transmissions.

Radiant barriers work. I installed the barrier in an old house and afterwords was able to spend 2 or 3 hours at a time up there rewiring the electrical in July. I replaced the knob & tube wiring with romex so I could blow insulation on top of the wiring. I blew in 8" of cellulose and need to add another 6" but it's a lot better now than when I bought the place.

Sealing attic leak penetrations to the conditioned/living area below and adding attic insulation are certainly big steps that can have good payoff and improve home comfort. Tremendous amount great educational information and videos on the internet to help you along.

Being an older house, does your attic have any passive ventilation at all - for example ridge vents, turbine ventilators, etc? If not, I think that might be your top priority.

Radiant barriers can lower attic temperatures during peak summer temperatures as much as 15 to 25 F and I think would do great deal in improving home comfort however, studies show the payback on them really not that good and it seems some home energy specialists are not big fans of radiant barriers - maybe b/c of the poor payback. But if it improves home comfort …. I need to do some additional homework on this topic as I am considering it myself.

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ridge vents, turbine ventilators,

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Has ridge vents but no turbine

I am focusing on things on can do myself right now

Whirly birds will make a big difference. I had the old ridge vents that weren’t to good. Added 4 whirly birds and it has make a huge difference in house temp

This winter I removed all the blown in insulation and had open cell foam sprayed in. Made a tremendous difference. Before, the temps would get over 140 in the summer and humidity would always be high.

Here is a snapshot of the last 24 hours (temp, humidity, and pressure are recorded automatically every 5 mins or so)




it's rained pretty much every day for the last month

For those suggesting radiant barriers...we live in a home built in 1904 that had a second story addition about 10 years ago. The second story is setup with kneewalls on 2 sides.

Should the insulation be on the kneewall or the attic roof side? Additionally, if the kneewall side is insulated should I tack the radiant barrier to the roof rafters against the roof?

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Has ridge vents but no turbine

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That’s good - I suppose the next thing to verify is that you have sufficient ridge vent area and soffit intake vents (and that the soffit vents aren’t covered by insulation. Attic Venting Calculator

And should at some point consider a powered attic ventilator I suggest you read this first. LINK

Nice little publication to help you get started with your roof sealing and insulation project(s). LINK

I had Diversified Energy come in to do the work. It was $3200 for the insulation. I think the total coverage was about 2000 sq feet, 2 story house and the roof has all sorts of goofy angles.

We opted to remove the existing blown in insulation ourselves using a big harbor freight dust collector system (I wanted one for my sawdust making shop) that was like $250 or so. Saved about $500 and I got a new toy. Removal time was probably 8-12 hours, the wife stayed downstairs changing collection bags and I vacuumed every scrap of the 6-8" of insulation. 2 truck loads to the landfill since I couldn't find anyone that wanted to re-purpose it at the time.

Anyone had this done recently in the Houston area, or any area really, by a company that can tell me a ballpark price per square foot on air sealing/blowing in cellulose?