Roof Overlay - looking to add insulation

[JavaBrewer]

So our 70's era home had an addition at some point ~ 20' x 20'. The walls are block and the previous load bearing beam was replaced with a giant beam spanning the addition opening. The old exterior wall was maintained and access to the room was through the original exterior entry door. When we bought the house we demo'd the interior and removed the old exterior wall which was not supporting anything. Now the bonus room is fully integrated as a family room with our kitchen.



The issue is that in the summer months the room is very very warm. The roof is not insulated and heat is pounding from above. Our home AC runs all day - the rest of the home is comfortable but this area is not. The bonus room roof is not pretty - but it does not leak and walking on it does not present any clues to damage or rot.




So I have been considering options to provide more insulation and protection from the heat and elements.

1. Have the red clay tiles added to the roof. Visually that would integrate with the home but I doubt the tiles would do much (anything) to provide heat insulation. I got a quote a few years ago at ~ $4K to add the tile.
2. Add solar panels to the home. I have read they reduce up to 30% of the heat and of course I would benefit from the electric bill savings. I'm not into this due to expense and we don't plan to live here more than another 5 years so don't want to invest that much $ (have other projects to complete).
3. Have a second roof added with pre-made truss, low pitch, max out insulation, and cover with red clay tiles. I'm guessing $10K-$15K here.

Does anyone have other suggestions or recommendations on my options above? I will be looking for a roofing contractor in the coming weeks to provide a real estimate but thought I could toss this over the fence here for some early opinions and feedback.

Thanks Pelican!

[id10t]

Adding the red clay tiles on top wtih a spacer of some sort (2x4?) will shade your existing roof (less heat/energy transmitted to it) and provide circulating air underneath (minimize heat transfer from red clay tile, keep things from growing in the dark and moist, etc)

Code may have dictated the roll paper instead of clay tile on the addition - in which case you might need permits, etc. to make any change up there. Especially since part of the run off of your peaked roof area flows onto your flat roof area.

( when my roof was redone, the county permit person didn't even get out of the car and measure, just said "that is less than 2:12 use roll paper instead of shingle" and wouldn't hear it from my roofer... who as someone wiht a masters in math probably knows how to properly measure and calculate rise over run... )

[Evans, Marv]

Seems like most of what you are considering involves $$$ and major changes, so I'll throw this out for your consideration. My roof is a low pitch, bituminous membrane - which means it's black. In the sun out here in east S.D. County at about 10 AM, the temp would be 160 to 175. I applied glacial white, elastomeric coating to it, and the temp went down to around 100 to 110 at mid day. I had to put down two coats of asphalt emulsion (applied @ right angles) followed by two coats of the elastomeric coating. It didn't make it freezing inside, but my attic fan went on at 3 PM instead of 11 AM and the AC kicked in after 3 PM instead of mid day. You don't have a lot of area, so the cost wouldn't be a lot. The best coating at HD runs around $135/4.75 gal container & reflects something like 85% of insolation. The coatings would extend the life of the roof too. Another possibility would be investigating having a foam/Styrofoam layer applied, but that would raise the roof a couple of inches and maybe need to have the drainage from your tile modified. An added possibility would be to add a foam layer insulation to the ceiling and make it look like part of the room.

[javadog]

I would frame a gable roof over it, perpendicular to the existing gables. This would require some re-work of your existing tile roof. I'd finish it with matching tiles and I'd insulate below it.

You'd probably want an architect to design it.

The existing roof design for the addition is a problem waiting to happen, and a bit of a negative cosmetic issue for the house as a whole..

JR

[nota]

white roof paint will lower the temp's
cheap eazy and quick
even lite gray gets hot

I did my house and saved about $100 in summer ac costs vs the gray shingles

are the skylites double panes ? that can help

old sail to shade that area ? plant a tree ?

[968rz]

I think the gable option would be best as I don't think the tile works very well on a flat roof

[Scott Douglas]

We have almost the same situation with our 17x22 family room. Our beams look like they may be deeper than yours though. We had foam added to the flat roof when we had it re-roofed. Increased the pitch slightly by doing that. Room still gets warm. We have knotty pine between the beams which I haven't wanted to cover up. Our A/C is ducted in in-between the beams now. If my wife insists it is too hot still, I might consider a drop ceiling that would come down 3/4 the depth of the beams so we'd still have the look of beams rather than a flat ceiling. Could pack the insulation in the space created by the drop. I wouldn't want anyone walking around on my flat roof to put in solar or whatever. I paid too much for it not to leak to allow anyone but myself or my roofer up there.

[Evans, Marv]

The elastomeric covering and insulating the ceiling might be the best option. Even if you go the construction route, you'll still have to insulate - and maybe that would include the ceiling. Since you say you're not going to be there for more than five more years, I wouldn't do anything that wouldn't give an ROI - which is the smart way to go in any event. Here's a pic of part of my roof.

[bpu699]

Easy fix, did this to a 2500sf office building...

The roofer laid 4 inches of the pink foam sheet under the membrane. Cost next to nothing, works great. Plus, the foam last forever, and is an additional water barrier.

The foam sheet is available at home depot, probably 20$ for a 4 by 8 sheet.

Bo

[tcar]

Originally Posted by bpu699

Easy fix, did this to a 2500sf office building...

The roofer laid 4 inches of the pink foam sheet under the membrane. Cost next to nothing, works great. Plus, the foam last forever, and is an additional water barrier.

The foam sheet is available at home depot, probably 20$ for a 4 by 8 sheet.

Bo

The foam is NOT a water barrier. If water gets through the membrane, it goes all the way through.

[tcar]

When the room was added, was extra A/C added? That's a good sized space just to tack on an existing system.

Sounded like it was added before you moved in.

Also, where are the diffusers? Returns?
That could be part of the problem.

[JavaBrewer]

Everyone, many thanks for the response so far. The A/C unit looks pretty new. I should check the date stamp. That said the AC was originally excluded from the bonus room when we bought it. I am guessing that is why the PO did not tear out the original exterior wall. In the summer months they just closed the exterior door to that space and used AC to cool the original home. Now that we integrated the room into the home we added a diffuser to the space bringing count to 3 (it's a large space) and added one return that sits directly below (floor level) a diffuser (ceiling level). No doubt this a not helping our situation but I don't have many alternatives due to space and layout.

I really don't want to add anything to the ceiling as it would reduce or eliminate our exposed beams which tie in the rest of the home aesthetically. I'm interested in the elastomeric coating but as pointed out our existing roof line visual sucks which hurts resale. Can't beat the cost and simple application though. Will think on that one.

[sammyg2]

Originally Posted by Evans, Marv

The elastomeric covering and insulating the ceiling might be the best option. Even if you go the construction route, you'll still have to insulate - and maybe that would include the ceiling. Since you say you're not going to be there for more than five more years, I wouldn't do anything that wouldn't give an ROI - which is the smart way to go in any event. Here's a pic of part of my roof.

This ^^^^


Grandparents had this on the roof of their house in Las Cruces and it worked awesome.
They laid down or sprayed a thick stiff foam insulation and then put a white rubber membrane over it and sealed it all with white goo. That's the technical description.

Wasn't all that expensive to install or maintain either.

[Dantilla]

Originally Posted by sammyg2

white goo. That's the technical description.

I've been applying this stuff over a roof this Summer, buy my terminology must be wrong. I've been calling it "Wonder Goo".

[look 171]

Originally Posted by bpu699

easy fix, did this to a 2500sf office building...

The roofer laid 4 inches of the pink foam sheet under the membrane. Cost next to nothing, works great. Plus, the foam last forever, and is an additional water barrier.

The foam sheet is available at home depot, probably 20$ for a 4 by 8 sheet.

Bo

omg

[look 171]

insulate between the beams from the inside. Rigid foam or spray foam will work. I like spray form. I think its superior. Install a ductless HVAC just for that side of the room since your AC is taxed to the max. You can roll that "Whitegoo on there". it will help but something looks funky between the addition and the main house. You will have problems there in the long run. It becomes someone's problem in 5 years and it should hold out for that long.

I know, covering those beams is out of the question.

[sammyg2]

Originally Posted by Dantilla

I've been applying this stuff over a roof this Summer, buy my terminology must be wrong. I've been calling it "Wonder Goo".

Oh, so you went with the upgraded version. Smart move.
It's a little more money but worth it.

I was considering upgrading to the "super goo" but I couldn't justify the big $$$$

[Baz]

Originally Posted by look 171

Install a ductless HVAC just for that side of the room since your AC is taxed to the max.

This is what I was thinking. Your main problem is the air conditioning.

A mini-split ductless system would solve that problem.

[javadog]

I'm still going to recommend you re-do the roof to integrate the addition onto the house. Right now it looks like an DIY addition and that hurts the vale of the hose. No archtitect would have designed that if the addition had been part of the house from the beginning. To a lot of buyers, myself included, DIY usually translates to "done poorly and cheaply." I'd fix the roof, add insulation above your exisiting ceiling, rebalance the airflow from the existing HVAC system (including any ductwork changes needed) and then see where you are.

Something along these lines:



An added bonus is you get rid of the skylights, which nobody wants anymore.

[bpu699]

Originally Posted by tcar

The foam is NOT a water barrier. If water gets through the membrane, it goes all the way through.

Actually, if you use seam tape, it is an additional water barrier... Every little bit helps...

This solution is cheap and easy...