Roof Overlay - looking to add insulation
 

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.

http://forums.pelicanparts.com/uploa...1469555633.jpg

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.

http://forums.pelicanparts.com/uploa...1469555686.jpg
http://forums.pelicanparts.com/uploa...1469555700.jpg

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!

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... )

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.

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

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 ?

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

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.

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.

http://forums.pelicanparts.com/uploa...1469569012.jpg

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.

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.

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.

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.

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

omg

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.

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 $$$$

:D





http://forums.pelicanparts.com/uploa...1469628141.jpg

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

A mini-split ductless system would solve that problem.

<iframe width="853" height="480" src="https://www.youtube.com/embed/nsem0_09YKc" frameborder="0" allowfullscreen></iframe>

<iframe width="853" height="480" src="https://www.youtube.com/embed/ozaw9QhxkQU" frameborder="0" allowfullscreen></iframe>

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:

http://forums.pelicanparts.com/uploa...1469630442.jpg

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

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

This solution is cheap and easy...

Yep, I agree, but not sure if he's going to recoup that money in 5 years when he sells?

NOOOOOOOO (using all my lung capacity)

This is pretty common, and people have been doing it for at least 20 years.

It is literally true that the pink foam sheets are not capable of absorbing water and has a life span of at least 50 years.

Some roofers and people who do energy retrofits to existing houses use this method . Of course you want someone to do it who knows the technology.

I bet that an array of solar panels would shade that roof pretty well.

Should add value to the home as well.

One way to fight high A/C bills, kind of backwards but conventional solutions have already been addressed in this thread.

Ok, I give up...

I gave you guys a solution that's used in the Midwest on commercial buildings... I have had the roofs on my office buildings done this way...

Works great, affordable, and provides a decent R-rating. The pink stuff is strong enough to walk on (they use it as underlayment for highway), its cheap, and works.

The taping of the seams isn't meant to be waterproof... the rubber membrane roof that goes over it, is the water barrier. The pink stuff works as insulation... I said the tape add ADDITIONAL water proof barrier...

We have renovated multiple commercial properties, and multitudes of homes. I speak from experience.

If you guys wish to find other alternatives that are way more costly, like redoing/reframing/repitching the entire roof or insulating from the inside, go for it.

I can give good advice, I cant make you take it.

Bo

Well, it is true that commercial roofs often use foam under a membrane. I disagree about the longevity claims. I've never seen a foam that lasts 50 years, but then again your membrane won't last that long, either. If you rely on the tape as adiitional waterproofing, you're using the wrong membrane. If water penetrates the membrane layer, your're ****ed.

As for the "good" advice, look at the bigger picture. Nobody (WITH A BRAIN) builds a house that has a tiled gable roof butted up next to a flat, commercial roof. The flat roof is an eyesore, no matter how you cover it.

Adding a pitched roof may cost more money but it will increase the value of the house. Enough to get his money back? Who knows? if I were a potential buyer, that roof he has now would make me walk away; I wouldn't even consider that house, I'd go to the next one.

He doesn't have a roof leak problem (yet), he has too much heat. If he wants to fix that with the least cost, adding more A/C would do that cheaper than a new roof. Yes, it's an additional bandaid that does nothing to improve the saleability of the house (thinking of a small, add-on A/C unit here...) but, if low cost is the goal...

You don't fix a mistake by making another mistake...

JR

It's more involved. The new ridge will want to go all the way to the existing pitched roof, (2 gable ends as you've shown would look funky and be hard to make waterproof) and check out what's involved with that existing roof: A skylight and a second ridge that's probably left over from the addition that was improperly solved and needs to be addressed. If I was only going to live there five years, I'd install membrane outside, insulate from the inside, install a new lid inside on and add a mini split.

You're interpreting my drawing incorrectly. What I was attempting to show is exactly what you suggest. The new ridgeline goes all the way back to the exiting ridgeline. What you are seeing as another gable on the back side is actually the line of the valley between the two roofs, not the edge of a gable on the other side. It just happens that the perspective in the photo makes it looks like what you mistook it for, not what I intended.

There's definitely some work involved,as the existing gabled roof is overly complicated, which is why I suggested having an architect design it.

I also have a house that was built in the 70's and ****ed up by previous owners. I spent a bunch of money to undo all of the mistakes and turn it into something I could live with. I'll never get all my money back, nor do I care. I chose not to live in a lipsticked pig and I'm happy with that decision every day.

JR

Thanks for all the great information. If folks are interested I will post 2-3 more pictures tomorrow to give a better understanding of current situation. The two tiled ridge lines in the picture are the garage (left) and home (right). I don't agree that this was DIY and thus 'poorly done'. I have seen my share of crummy sun room additions and this looks nothing like those. From inside the home the transition is pretty seamless and carries out the exposed beam to match other rooms in the house. The addition is fully integrated into an extensive backyard remodel so I'm guessing it was done at/near the same time. This work was done by the original home owner (according to neighbors a Marine who was OC) not the PO that I purchased from. Those folks were indeed a cheap DIY crowd and I have spent tens of thousands of dollars reversing their crazy work. Total rework of the electrical was needed - lucky the house did not burn to the ground before I got that done. :eek:

Edit - I went back in time with Google Earth and there are some early pictures that indicate this roof had tile at some point. I am guessing that the PO had a leak at some point and cheeped out on the fix declining to put tile back up there.

I agree with javadog that aesthetically it's an eye sore. But from ground level (that shot was taken standing on backyard slope) you cannot see the roof. Thus my thinking of adding tile but only if it could be done to reduce radiant heat. Solar panels I am guessing are going to blow my budget. I would have to buy them rather than lease if we are selling the home in ~ 5 years. They would reduce my AC bill though - last month $475 - normal no AC my elec bill is $175-200 (I have a pool). If I were going to stay here to retirement I would definitely pull the trigger on a new roof that integrated with the existing. I like things done right. I'm waffling on the paint - appreciate the suggestion but I'm back to appearance with a nod to cost.

Edit #2 - the roof is not flat. It is sloped away (down) from the home to the rain gutter just visible. The rain gutter drains into lines that go under the concrete patio and pool area.

NO!

It does not. None!

But it sure makes it harder to find leaks.

Explain to me how laying 4x8 sheets of 4 inch foam edge to edge, sealed with DuPont waterproof tape, does add additional water protection...

Usual construction:

OSB...

Then +/- tar paper...

Then 4 inch of foam rigid insulation...

Then (optional) seal joints

Then 1/2-3/4 fire barrier insulation...

Then rubber roof membrane/torch sealed...

Then white elastomeric paint...

I don't mean to offend. Here's where I am coming from, with the experience of 40 years in the construction business.

No good architect would have designed an addition like that.

The "flat" roof doesn't have near enough slope for a tile roof. Again, that's not a design a pro would have done.

The existing roof material is about as lousy as a roof material gets. As small as that roof is, there were a number of better choices.

Insulation is not a new thing. Even in your climate, it's needed. A flat roof can be properly insulated. Yours wasn't.

The lack of A/C speaks volumes about the original design.

All I'm trying to do is direct you away from the sort of thinking that got you in the predicament you are in. Given the stupendous cost of real estate where you are, fixing this would be a drop in the bucket in comparison. The framing doesn't have to accomodate any huge loads, the new roof could be framed and decked in a day and tiled in a second day. Not a huge deal, really.

JR

Why would you want to put elastomeric paint over a roof membrane? That's nuts.

JR

Perhaps its something else? Its that reflective white paint they use...?

Bo

Elastomeric paint is usually applied over a hard surface.

Rubber membranes are laid over foam insualtion. They can be loose, they can be bonded to the substrate, but they are usually glued at the overlapping joints and you don't paint over the top of them. They come in white, anyway, as well as other colors.

JR

Are we talking about rigid foam insulation under roofing? that we do to flat roofs all day long out here

Summertime Update
 

My summertime 2018 update!

I have decided to tackle this from both sides. I am going with the white elastomeric coating on the outside and rigid foam between the beams on the inside.

Jeff, is the spray foam a DIY item? Where do I source the materials and spray equipment...it sounds messy. I am leaning to a 2" thick rigid foam install - local Lowes sells it in 4'x8' sheets for ~ $25. A simple utility knife to cut and wedge between the beams. I plan to cover the insulation with pre refinished white ship lap (or similar T&G product) that is also sold at Lowes.

I am thinking R-Tech or this Kingspan: Lowes Kingspan 2" 4x8

So my plan is to finish nail 1/4 round ~ 3" from the ceiling on each inside beam - painted to match. Beam spacing is ~ 17-18" ... have not measured yet. Then cut and slide the insulation (metallic side facing up) into place lengthwise. I then wrap up the install by cutting and fitting cross wise T&G boards into place supported by the 1/4 round. I will make temporary panels of insulation and finish boards to fit into the skylights that we can remove once the summer heat is done. No nails or adhesives on ceiling or products other than the 1/4 round with finish nailer into the beams.

Does that sound reasonable? Any suggestions? I will sill have ~ 3" of exposed beams to look at which we can live with if we knock down some of the heat.

Again, if we were planning to retire here I would spring for a new roof and a modern mini-split AC unit. Yes the exterior view of the roof from elevated part of the yard is an eyesore but not something I can address without big $$$ to plans, permits, and labor.

Thanks,
David

http://forums.pelicanparts.com/uploa...1532371803.JPG
http://forums.pelicanparts.com/uploa...1532371803.JPG

David. I'm wondering if you can get a higher insulation value using regular fiberglass batting. The foam sheets only have a rating of R-10. I know I have six inch studs with R-19 insulation between them. Just a thought. I'd imagine you might be OK with less than 3" of the beams exposed, since it's just a visual to break up the ceiling expanse.

Some good advice.
We have a lot of additions like this in Florida and most are done with poorer construction, the “Florida Room”.
I agree flat roofs are crap, make no sense. If they leak you usually don’t figure it out till there is substantial damage. If you keep an eye on them and stay ahead on maintenance then not so bad. The idea of foam and rubber membrane is not so bad. The white reflective paint is used a lot in Florida and does help significantly bring down on your AC bill.
Adding a sloped roof will not be cheap. I would get a price and then make a decision. You’ve got at least three options so far.

I would try 3" to get a lil' more R value in there. It will help a lot. The spray foam is DIY but messy. Rigid foam can be cut with a knife, but we use a table saw. If you don't have one, use a fine tooth hand saw. It cuts easily. Are you painting the ship-lap or tongue and groove to match the beam? You have T-111 plywood on top of those beams now, why not save yourself a lot of work and install T-111 on there, paint to match it white or what ever color you (I should say your wife) like and be done with it. Yea hold it with 1/4 round. If you want to go with 3" foam, then you can extend the beam and fake it by making a U shape piece and nail it on the side of the beam and eliminate the 1/4 round all together. Its all DIY and requires a table saw, glue and some nails. Paint to match. You know how to get hold of me. I am always available