Please see the attached picture. (NOTE: This is NOT my house…. someone asked my opinion).
Situation is this: Block foundation, then sill, then cripple wall of approx 18″, then floor joists, then wall. House has original wood lap siding down to the sill plate. Outside grade is right up to the sill plate with a cement patio right up against the foundation. The house has now been vinyl sided from top of cripple wall and upwards. At some point in past, the cripple wall area downward, still with wood lap siding, had a wire mesh cement “parging” or stucco applied. That area has crumbled and has been removed, revealing the lap siding. The homeowner wants to re-stucco or cement parge this area.
Can cementboard (like for bathroom tile work) be applied there and then cement parging be applied? What kind of mix should be used?
I know, I know. This is not a “Fine Homebuilding” situation. I told them that the grading is too high and should be below the sill, and that the siding SHOULD have been applied all the way down to the sill. But they dont have the money for the regrading. They bought the house this way. This is what it is – whats the best thing for them to do to cover back that cripple wall? They WANT the look of that area being cemented as if it was the foundation.
Replies
(bump - new security procedures delayed this post from appearing in timely fashion)
Patch,
Nice pic...or should I say diagram.
I can't say with certainty that cement board would work, simply cause I never have done that...but really, I don't know why it would not work?
I can say with certainty that you definately could reparge the wall. First, wrap the lap siding with 15# or 30# felt paper. Don't use chicken mesh wire...use diamond mesh wire instead. Use stainless steel drywall screws to attach mesh to lap siding. Don't skimp on the screws...you don't want them to rust out...which is usually one of the causes of stucco failure.
For the mix, use Type M portland cement, and mason sand and use a liquid binder, like Acryl 60 as a water substitute. As for the proportions, If I remeber correctly, I used a 3:1 ratio ( 3 parts sand to 1 part cement).
There are ready mixes made by Quickcrete for stuccoing. You could even use a product called Thoroseal...but I've noticed some cracking associated with the use of this product after a few years. B-Bond, a cement product with cut fiberglass in it, also makes for a pretty good parging. Ask your local brick/block supplier what formula he recommends for your region; they are bound to know what works best.
IMHO, the mesh/stucco will give you just as durable a finish as going the cement board/stucco route; and for a lot less money and labor. ( you would have to tape and fill all cement board seams prior to stuccoing to avoid telegraphing.)
If you are concerned that the lap siding needs to be "padded out" a bit so as to use less stuccco material and/or for aesthetics...then nail on some ridgid insulation board overtop the lapsiding. ( I would still felt the siding first, then nail on the insul)
Hope this helps.
Last November I installed 1/2 inch plywood as a skirt board to an out building. Overtop the ply, I used 30# felt, which I stapled on, and then installed the diamond mesh and stucco as earlier described. This building is adjacent to another building that has a concrete foundation. Visitors have been unable to tell the difference...only by knocking on the plywood, can you then tell this was a stucco job. ( bit of a hollow sound you know is a dead give-away)
LOL.
Davo
I would first recommend removing the original lap siding. Instability and movement in this layer could well be the reason the old parge coat failed.
Then try to scrape down to clean the top of the foundation wall by a couple of inches.
Run a layer of ice and wate shield up from there on the sheathing of the cripple wall.
Then you can do a new stucco finish. I think that parge is a term more properly used term for applying over masonry wall, which this is not.
Also, Hardiboard not only makes lap siding, they also make Hardipanels which have a stucco appearing finish. That could be worth looking into if distributors in you area can supply it.
Excellence is its own reward!
I've got to say as well, nice sketch. What program did you use to do that?
Piffin's idea about stucco-look board was one of my suggestions; I've seen this done on garden sheds to make them 'match' the look of the main house which was stucco finish. For a fake, it's not bad. Considering they've already got *&?%$?% vinyl siding, WTF's the difference if they add some more fakery....
Another way to do it is to put a plywood skirt over the lap siding--still better to pull off the siding and mount the skirt directly onto the cripple wall sheathing (over a layer of felt unless it's Black Joe)--then paint a stucco-finish paint like MF's ISO-TEX on the skirting. He'll have to 'tape' the joints just as if it were gyprock, but joint compound won't work in an exterior environment. Use a product called Wallpatch (The GH Company, Missisauga, Ontario) which tapes like a dream and almost doesn't need sanding. Stainless screws to hold the skirting on or he'll get rust-through at screw heads. Prime the wood with MF's recommended primer, then either roll or trowel on the Iso-Tex to get the stucco pattern desired. Very easy, and not expensive compared to the alternatives. The Iso-tex can be painted any finish colour desired, or left its natural brilliant white. If properly applied, the stuff is almost bulletproof.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Thanks for all of the replies. This is exactly the types of info I was hoping to get.
I created the diagram with MS Paint. Just used my "calibrated" eyeball-to-mouse-hand coordination. Saved it as a small ".gif" file (as opposed to Paint's ".bmp" default which makes a HUGE file), cropped just the sketch area.
To Dinosaur: What is "Black Joe" ?
Thanks again, all, for the replies.
Walk Good,
Phil
'Black Joe' is a tarred paper board that you could think of as ½"-thick building felt. I personally don't consider it particularly structural but many building codes do; it's inexpensive and weatherproof (for a couple of years, anyway) so you find it used as exterior sheathing in lots of low-budget houses built in the last 30 to 40 years. BP makes it under the trade name Cascade, if my memory serves. The name 'Black Joe' comes from a brand name, and like Aspirin or Kleenex, has passed into the vernacular. This may be a Canadianism, like 'gyprock'; I don't know what you call it down in the States.
Thanks for the heads-up on MS Paint; I've got it but I never played with it seriously. Looks like it might be worth the effort, from what you produced.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?