Pre-code house with hot wall
BuckeyeBeaver
| Posted in Energy, Heating & Insulation on
Our house was built in 1972, before Oregon had energy codes. The exterior walls are 2×4 with some insulation. The mostly western exposure has no windows and gets hit with afternoon sun.
Would it make sense to remove the T-111 siding, add 2x2s, and replace the old insulation with new, thicker bats before putting the T-111 back?
If I did that, would I need to fasten the 2x2s with something other than nails? (I’m guessing that the load of the T-111 still needs to be carried by the original 2x4s.)
Is there a better way to deal with my problem?
Thanks.
Replies
Depending on your specific vapor barrier needs, you might consider just building the new wall on top of the existing. Use rigid foam, long screws, and new T-111.
I'd rip a 2x6 into (2) true 2" wide strips, and screw through them, the existing T-111, and into each old stud. 2" of foam tight between each.
I'd be tempted to leave out the scab studs, and just attach a strong 2" wide ledge at the bottom plate, and just GLUE foam solid to the wall, and then screw on the new T-111 through the foam and old T-111 and into the old studs.
Make sure you keep the screws from pentrating more than an inch or so into the old studs to avoid wires and pipes.
Batt insulation's just not that well thought-of anymore
Forrest
Why wouldn't you simply install rigid foam and the new T1-11 screwed/nailed through that? Seems a lot of work to fur it first, then cut the foam to fit, etc.
Yep. I hadn't thought of that. I suppose I was just thinking about recycling the old T-111, which would be a lot more work!
Sounds like just adding on top of what's there makes more sense. I'll give that some serious thought. Thanks for the ideas.
Your second poster hinted at a simpler solution, I think. Since the existing plywood gives you shear strength (and probably your vapor retarder), simply adding to that may be the easiest rather than tearing out and adding to. Your concept is sound and straight forward, but I'm thinking much more simple, maybe. You can nail the 2x2 to the studs ... that kind of thing is done all the time. But maybe consider adding on rather than tearing out.
Yes. You all have been thinking more efficiently--from an amount of work to do standpoint--than I have. I'm glad I asked here before just tying in and trying to take off the T-111 with the intent to re-use it.Thanks again to all of you.
Hi Buckeye:I was faced with a similar situation about 4 months ago. The plan was to tear the stucco off, then tear off the sheathing, fur out with custom cut 2" (actual) stock over the existing stud bays, add insulation and resheath.Instead, I tore off the stucco and found it MUCH MUCH easier to leave the 7/16" plywood sheathing up (it was in better shape than I expected, even after beating the hell out of it to remove the stucco.) We then nailed up standard 2 X 2s (1.5" thick) through the sheathing and into the underlying studs. We filled the new bays with rigid 1.5" insulation (which took almost no time at all to rip to width) and put new sheathing on top.The advantage here is that we ended up with a new wall that was an equivalent thickness to a 2 X 6 stud wall. That makes it a lot easier to retrofit windows and doors without having to buy or build custom jamb extensions, etc... -t
Like I always say ... pay your money, take your choice. If you got more time than money ... do it your way. If time is precious and you have some $ to do it, save the time.
I have bumped up the insulation thickness in older 2x4-framed homes a fair number of times, but I do it from the inside. Gyprock is easier to strip (and cheaper to replace) than siding and sheathing, and you don't disturb the rain-screen/housewrap in the process. Also, biscuiting on jamb and sill extensions to your windows and doors is a bit easier from the inside (you won't have to work from a ladder or set up scaffolding). Alternatively, if you're good at gyprock work you could just do gyprock returns.
You can nail the 2x2s to the studs, or screw them in place; structurally there's no real diff. If you have a screw gun or impactor but no nail gun, use screws. If you've got a framing nailer, it'll be a lot faster to nail it.
One other thought: Remember if you screw it you'll need at least 2½" screws, which are fairly long and driving large numbers of those through 2x2s into dry old framing will run down your batteries pretty quick.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Good point of view. The downside is that the inside tends to be somewhat less complete than insulating the outside (e.g. you don't get the rim joists or other odd things like intersecting walls. Again, pay your money take your choice. Each approach has advantages and disadvantages.
Sheetrock is cheaper and simpler to replace than an exterior. What I would do in your case (assuming you've checked into having it spray foamed) is tear off the sheet rock, tear out the fibertrash, replace it with foam and resheetrock.
Foam is far more effective than fiberglas even with the same R value!
This is a two-story wall with the stairs to the 2nd floor/basement in the middle of it. The living room is open to the ceiling, so it's a 2-1/2 story space that is tricky to reach because of the stairs. We painted it using ladders when we moved in years ago, but would probably need staging to do handle sheetrock. Of course, we'll need staging on the outside, too, but it will be easier to erect and work with, even though there's stairs to the lower deck.However, your idea does mean not having to deal with trim changes. And, I forgot all about the front door when I said that there weren't any windows in the west wall, so that would have to be built out.I suppose I could cut some holes in the sheetrock at each stud bay, and on either side of whatever horizontal blocking or plates there might be, fish out the old fiberglass, and fill up with foam from there. For most of that wall there are no wires or pipes, so that shouldn't be much of a problem.
Another option I haven't researched, but my wife has, is hanging some outdoor curtain material in front of the wall with an air gap behind it. She's seen something that is intended to block the sun from hitting the wall. Our climate is pretty mild. The last few days have us in the middle of a heat wave, but we don't need to run our A/C most of the summer. And, we have our setback thermostat set for 65/50 in the winter, and only run it in occupied mode for a few hours each morning and evening. We get a handful of days when we run the furnace 24 hours because we dropped down below freezing, but the typical low temps are in the upper 30s and low 40s and we like it cool overnight. The sun blocking curtain may be more cost effective, and sounds like a lot less work than opening up the walls.
My first thought is to ask what color the wall is on the outside. Roughly speaking, dark colors absorb about 90% of light energy into heat, while white and very light colors reflect about 90% of light energy back away from the building.If you're going to add thickness to the wall, I'd be voting for doing it outside. Given that your wall is tall, I'd install furring at least under the sheet joints (maybe just overkill). The right kind of plantings are another, if less immediate, solution. A knowledgeable tree person could probably steer you to the right deciduous tree to shade the area. I've also seen the problem handled around here (dry southern Colorado) by building trellis of some sort from the eaves down to a seasonal fast growing vine of some sort. Saw one place in the fall where they had grown loofa (sp?) and were now giving loofa away to anyone who wanted!
The walls are brown, which fits well with the woodsy setting we are in. We're overdue for re-staining and were thinking of going with a gray-green, which would move us closer in the white direction.The trellis idea is similar to the curtain idea, but with the advantage of transpiration helping to cool things. The only problem is a lack of a place to put the roots. At the base of the wall is the outdoor stairs leading to the lower level. Otherwise, I like that idea. There are really two, separate, west facing walls with a short, north facing jog between them. The northern section has a planting bed below it, so that would allow for a trellis, there.As far as trees go, we have plenty of 50+ year old Douglas Firs around the property, many of which do shade the house on the north, east, and south sides. But, there is a space, west of the house, behind the carport and garage (we have both) that is a steep hill with blackberries. While we could plant trees there, they are far enough removed from the wall in question that it would take a long time for them to grow enough to help. The stairs to the lower level, at the bottom, are higher than the ground level just to the west.
How about gluing aluminum foil to the T-111 on the west wall? That will reflect the incident solar gain that is causing the heating. Just kidding. The curtain idea has problems like wind, critters, fire, etc.Overlaying the whole wall with 2" of rigid foam sounds like the best solution so far. The key is to get the weather detailing correct so that water stays out/drains out of the sandwich. Doing the outside, like Forrest mentioned early on, is the best way to get a total thermal upgrade. This also causes a whole lot less disruption to your life inside the home than an interior solution does.If you do more T-111, you might consider coating it on the flat (paint or stain) before it goes up, and then again after it is up. Sealing all the edges is a key with plywood products because they all have endgrain that can funnel water into the panel.Bill
I like the foil idea. ;-) There's a photo in today's paper of a fellow who covered his wide-brimmed hat with foil. We had 106 or 107 degrees in greater Portland yesterday, so keeping cool is on the minds of a lot of folks around here.As to the wind problem, the curtain she's talking about retracts, so it would only be deployed when the sun was going to be a problem. But, I wondered about that aspect, too. Critters are also a consideration with the trellis idea. I suspect our exterminator would not like the access it would provide for carpenter ants.Good point about pre-coating the T-111. We did that when we remodeled our master bathroom. The old bathroom had a little Juliet balcony that faced the street. Why anyone would design a bathroom that faces the street with a door and a balcony is beyond me. For years we had a large flag hung on conduit attached to the front railing of the balcony so we could have the door open in warm weather. When we remodeled, we took out the door and the shower window next to it, expanded the shower across the width of the room, put in a couple of awning windows at the top of the wall, and covered the rest in T-111, which we stained on the ground before it went up. I think we remembered to coat the edges, too.
Your additional details are filling in the gaps. Mild climate in general, etc. Your idea of shading the outside ... since this is a cooling concern primarily, is really the best. Now is the time to brainstorm. Trees? How about lattice and/or vine? You could get eclectic ... but that wouldn't go w/ the 'woodsy' feel, I guess. You have a deck on that side? Maybe extending the deck up some would be an option. Think outside the box. Bamboo box planters along the wall ... oooh fast growing and maybe nice!
Regardless of furring out or not, consider shade on that side of the house.
By the way ... foil ... may reflect a lot of energy, but it may have low emissivity (much like the blade of a jackknife) and it could get hot ... which may be somewhat counterproductive.
Also the door is largely a non issue, really. Removing the brickmold/trim and extending the jamb is relatively a piece of cake. Don't let that influence your decision.
It didn't occur to me that I could post photos until I saw the photo of the scaffolding! So, to help explain the project, here are two photos of the west wall(s) of my house. As you can almost see from image 8120, the stairs going down to the lower level make it impractical to grow something on a trellis on that part of the wall.Not visible to the west (right) is the drop off, and then hill, currently covered with blackberries. Putting a couple of large trees on that hill might help, but it will take several years to get to a height that will make any real difference.I understand the concept of extending the jamb. It gets a little close in that corner, though (image 8121). It might work if I don't change the thickness of the small bit of wall with the windows.
More food. The proximity of the windows to the adjoing wall will affect how much you can 'pack out the wall'. I looks to be maybe just a couple of inches. The small north facing walls don't need to be touched in the project.
Sounds like the hill is too far away for trees to be affective. You can still put a trellis in, just don't grow anything on it. Got to think outside the box.
In the grand scheme, though, you really aren't in a cooling climate (I have a house in HR just east of you), and the need for the added benefit is only a handful of days a year (maybe this year is an exception?). Try to keep it simple and inexpensive. Maybe some other architectural elements that will effectively shade it. Be glad that wall isn't a window wall with that 'fabulous sunset view' ... you'd be begging for what you have now!
That was my thought, too. The north wall is too small, and only the 2nd floor part of it is in the living room. The first floor wall is behind a closed door to the basement. The orientation isn't truly north, but more northwest. Thus, it does get some late afternoon sun. We have a roll-up shade inside on the 2nd floor window made of "warm windows" material that does a pretty good job of insulating.We'll give that trellis without plants some thought. It might be the way to go. We'd have to leave the bottom of it 6 or 7 feet above the deck and outdoor stairs, but that's not where the worst of the sun is and, again, that part is the enclosed stairwell to the basement.Yes. Inexpensive is the only way to go. Otherwise the payback would be too long.As I hinted at, above, the west wall isn't really west but more south west. There are trees shading the sunset, but not the mid-afternoon sun.
As far as scaffolding goes you can either rent it or buy it.. I found out buying used scaffolding was cheaper than renting would be and since I have my own I've found a zillion things I feel much more secure doing on scaffolding. I'm 61 years old and I'd never paint on a ladder, however setting up scaffolding is very easy.. If you tire of the scaffolding you can most likely sell it for what you paid for it so it really costs you very little.
I had the opposite experience. I built a house just east of Portland and investigated extensively buying scaffolding in lieu of renting. Renting is dirt cheap. I rented scaffold for like 3 months for very little (I did have my own planks, though). I thought it very inexpensive and hassle free, really.
Three months? sure! If that is the only time you ever need them. In my house with 28 foot ceilings I need them every six months just to get up there to dust, not to mention changing lite bulbs and other tasks like cleaning gutters and painting trim etc..
I've had my set for 9 years now and would never be without them..
By the way did you use real scaffolding planks or just boards?
If it was just boards you are a brave (and foolish) man indeed!
Good points. Definately if you use them regularly, you probably don't want to rent. I personally wouldn't generally use them for tasks like cleaning gutters, changing light bulbs, or dusting, or painting trim; I'd just use a ladder, but it depends on your situation.
I made 2 nice scaffold planks using 4 scavanged mobile home roof 'trusses'. They were slightly curved and maybe 6" deep in the center. I glued/screwed 1 foot wide plywood to both sides. They worked GREAT, were lightweight, and cost me very little; 2 sheets plywood and the trusses were like $16 for the 4 at the rebuild-it center (I got lucky). It would be easy to build your own 'truss', too, though. They were like 12ft long, so they extended my scaffolding nicely (I secured them so I wouldn't 'tip') ... probably not OSHA approved, but it worked nicely. Here's a pic of them on one level scaffold. I used them on top of 3 levels for high spots. VERY handy and nice solid platform to work from.
Edited 8/2/2009 3:00 pm ET by Clewless1