Residing and Insulating outer walls

[Melitta]

I have looked through some of the other topics on residing and insulating, but I have a few more questions and all the topics seemed to be locked. So here goes, we are looking into reinsulating and then residing our 1993 single wide 18x76 Fleetwood. We are the original owners. Our siding is falling apart by the windows and where the underpinning is (we missed out on the lawsuits for our siding). You can really feel the home heat up when the Texas sun hits the back part of the house around 2 O'clock every day. This really effects the living room, one bedroom and the kitchen/dining area. We did a metal roof, per Mark's book, about 4 years ago and 2 years ago had a new AC unit and furnace installed. We still can not keep our home cooler than 82-83 degrees when it gets into full summer and that is with the AC running all the time.

1. What is the highest/best insulation to put in the wall of the home that gets full sun at 100+ degree temperatures?
2. Once the siding is off and all old insulation is pulled out, how is the wall suppose to be layered? House wrap in between the studs, insulation, then siding?
3. What about the styrofoam panels for insulation instead of fiberglass?

Now for the siding. I am not a fan of vinyl siding. I am thinking of the Hardi cement siding because of our constant humidity. Is this a good choice? Is there another siding that would be better for high heat/humidity areas such as ours?

Thanks for any advice!

[Greg]

Hi. Since it is a '93 year model I am guessing that you have at least 2x6 studs.

I have mixed thoughts between fiberglass insulation and professional spray foam insulation. Foam will give more R value, but it is expensive - around $1/sq ft. plus once it is sprayed in the wall is effectively sealed tight for ever. I am sure others will add their thoughts on this.

If you stay with fiberglass, you will need undergarment under vinyl with tyvec between the underlay & siding. I have not worked with hardi board so I really can not comment on that. Remember the weight issue, you may need to add perimeter blocking for added support.

As I said I am sure that some that have worked with hardi board will add to this. Greg

[JD]

The highest rated insulation material would be polyurethane rigid panels. The problem with rigid panels is in filling the entire cavity between studs. There is the actual cut itself, which needs to be accurate, even if your framing is not. There are also electric wires, nail boards, and corner bracing.

If you are looking for the best practical insulation, that would probably be spray foam. It will give you the highest R value per inch and will do a good job of filling all nooks and crannies. This insulation also has draw backs. If they cut 1" holes in the walls to supply the foam and then put one of those plastic plugs in the hole, the hole will probably leak and the plug will eventually dry up and break apart. There has to be a better idea than the plastic plug. Just looking at it you can see these problems are coming. Another draw back is if you ever need to get into that wall for an electrical repair, the foam will certainly be a problem.

If it were me, I would be looking at high density fiberglass batt insulation and using reflective foil insulation on the walls with the most sun. In the old days, standard batt insulation for a 2x4 wall had an R-11 rating. The high density batt insulation for the same wall is R-15. The foil will probably do the most amount of good against the sun. There are many brands and differences in construction, but I would think they would be pretty much the same. You would want to get a multi layer product, 2-3 layers with air pockets. You would also want to get the perforated product so it can move moisture. Then when installing the foil, you want a 3/4" air gap on at least one side. I would be thinking to cover the outside of the studs with the foil, and then install a furring strip over each stud area. When you install your siding, the 3/4" gap will be there. I would think the foil could be used at the vapor barrier, but you will have to check with the manufacturer to be sure.

On the siding, I like the Hardie products too. I have a job coming up where a bus bashed a mobile home with aluminum lap siding. Aluminum siding is not supplied in California as best I know. So I am replacing the siding with HardiePlank. I have installed a lot of Hardie Panel, and like it very much.

JMO
JD

[Melitta]

Thank you both so much for the replies. You both have given me good information on what products I need to start looking at and pricing them. I know we need to watch the weight issue as we have already added extra weight with the roof over. Our neighbor bought some cement siding and used it as his underpinning. As he works ungodly amount hours, he just cut to fit under the home and let it rest on the ground. That was 3 years ago and it hasn't even acted like it is going to rot, mildew or mold. Once again thank you for the replies.

[Jim from Canada]

What I have done (2x6 studding) is replace the fiberglass insulation where bad with Roxul brand cellulose batts (higher R rating), then sheathed the outside of the studs with 7/16 exterior OSB and then a layer of 3/4" exotherm (polyisocyanurate with foil face), then siding (vinyl). I "Tuck" taped the exotherm as it acts as a air infiltration barrier.

[Melitta]

According to hubby, we have 2x4 studding. Since this posting is about us insulating and trying to keep our cool air in the house, here is another question. We replaced the AC two years ago. At first we had great air flow again, then a few months later, we were back to low air flow in the living room, kitchen and our bedroom. Since the AC was still under warranty, I called the AC company. Explained the loss of air flow again (which is why we replaced the unit in the first place), once they got here they said, "You have a freon leak, that is why it isn't cooling, not because of loss of air flow." I told them, "I have had this home since new, I know what air flow should be coming out of these vents and it isn't happening." They insisted it was a leak, and didn't check the ducting. They fixed the "leak" and left. When the company replaced the furnace, when they pulled the furnace out, they told us, that the main duct under the furnace had holes on both sides where the "tape" had come off and that is why we didn't have any air flow to the back part of the home. At the time, I figured we had a hole somewhere, cause you could feel the cool under the house when pulling the underpinning, we just couldn't find it. Right around the time we noticed a loss of air flow with the new unit, the toilet closest to the furnace had overflowed and the water went straight into the vent. We pulled about 4 or 5 shop vacs full of water out of the ducting. I think the shop vac is a 5 gallon. Is there a simple way to check to see if the weight of the water might have pulled the main duct tubing down from the furnace? Or am I going to have to call an AC company to come out again, have them pull the furnace to see if that is what happened? We have gone under the home, but we can not position ourselves where we can see, the home is less than two feet off the ground in that area. Since putting in the new furnace and AC we replaced insulation and plastic on parts of the underneath that was missing. Now, we can't "feel" if we have a leak or not just by pulling the underpinning, the way we could before.

[Greg]

The easiest way to do a quick inspection is with a mirror & flashlight. Remove the floor vent and use the mirror to check the duct work to the next vent. go from vent to vent and check it that way. If you are in a double wide there should be a duct that connects the 2 halves, you may need to check that from under the home.

Try to stay away from the "Tape repair" job if you find a leak. I rather use patches with screws or pop rivets. Greg

[Melitta]

Thank you Greg! We have done the flashlight and mirror check, but aren't finding anything. We did the flashlight and mirror with the old AC and never saw that the duct work leading up to the furnace had holes in it. I can see where the duct connects with the furnace, but can't actually inspect it without either removing the furnace or somehow contorting my body into an ungodly position in order to get under the home. Fortunately, we had a friend stop by and informed us that his nephew owns his own AC business and would have absolutely no problem commando crawling under the home. LOL. He is going to stop by and see if he can find anything. Thank you to all who helped me out. I am crossing my fingers that our friends nephew will find something.

[Robert]

IF problem is still unresolved, what is the furnace model number ?


Thanks,
Robert

[Melitta]

RB15C with a serial number of WOM8455442. Coleman.

We have not yet heard from our friends nephew, but our friend's infant granddaughter is in the hospital with a condition the doctor's can't figure out. Our friend and the parents to the infant aren't getting much more information other than, her prognosis is probably fatal. SO, we aren't wanting to "bug" him about his nephew coming out.

We have put a "wind machine" fan in the hallway near the kids bathroom (that is where all the airflow is) to help push the air down the hall into the rest of the house. It is helping some. What doesn't help is the 102-104 temperature everyday. LOL. I keep it set at 82, if it runs constantly I kick it up to 83. I know the heat and humidity are a big factor, but if I even tried to keep it at 80 or even 81 it would run from around 2 pm until 7 or 8 pm and never turn off. At night I am having to keep it at 80. 78 or 79 it runs alot and we get down to 75 at night for an outside temp. Not understanding why it would constantly run set at a hotter temp than it is outside.

[Robert]

Heading to the doctor, will check back and see what I can do this evening.

Furnace model number most likely EB15C, recheck that please.

Saddened to hear of the childs sickness, prayers for her and the family.



Thanks,
Robert

[Melitta]

You are correct, EB15C. I was going off the techs handwriting on the paperwork. His E's look like R's to me.

Hope doctor's visit goes well!

Thank you for the prayers for their family, they really need them right now.

[Robert]

Hi,

You can remove screws from bottom side flanges of blower assembly, disconnect wiring molex plug and slide blower assembly out.


Then mark and disconnect wires to allow removal of both heating element assemblies.


Then you can get a look at duct connector under furnace to duct trunk line.


For best view, hold digi camera or video cam in there and take pics or video.



Place on computer and take a look.



Water is heaviest there is and that much weight on those flimsy ducts can pull loose easily.



Thanks,
Robert

[Melitta]

Thank you so much Robert! We will give this a try this weekend. Thankfully we are suppose to get some cooler weather after today. Ha,ha...if you call 90ish degree "cooler", but beats the heck out of 100+!

I have one more question. Is there a purpose for the register covers to vent the air side to side instead of letting it blow straight up? We have been thinking of replacing all the covers to ones that don't have the slats angled left and right. If we go with ones that allow the air flow to go straight up, that won't hamper the air flow return to the furnace would it? I ask this because when we pull a cover, the air flow coming out of that opening almost doubles.

Thanks again for your help!

[Robert]

Hi,

You're very welcome, happy to help. The airflow blowing straight up has increased force out of the register.

Angled slows that and helps with air movement as it leaves register.

Forceful airflow can be a nuisance and not usually recommended for blowing straight out into living space.


The return air is most important in achieving comfort temp wanted.


Thanks,
Robert