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Acrylic Stucco vs Cement Stucco vs EIFS: What Each One Is Made Of, Layer by Layer, Where Each Belongs on an Ontario House, Cracking, Drainage and Installed Cost
Exterior Finishes
Three Things Called Stucco: Cement Over Lath, Acrylic Over Foam, and EIFS, Which Is the Second One With a History
When a homeowner in Ontario says stucco, they could mean three different walls. Traditional stucco is cement, sand and lime troweled in three coats over metal lath, the way it was done on houses in 1930. Acrylic stucco is a thin synthetic base coat with fibreglass mesh in it and an acrylic finish on top, over a foam base. EIFS is acrylic stucco where the foam base is an insulation board glued to a wood-frame wall, and the drainage behind that board is the whole reason the word EIFS makes some inspectors flinch. I finish most of my houses in acrylic, over ICF, and here is why, with the costs.
Side by side
| Cement stucco | Acrylic stucco on ICF | EIFS on wood frame | |
|---|---|---|---|
| Installed, mid grade | $21 | $13 | $15 |
| Builder / premium | $18 / $25 | $11 / $16 | $13 / $18 |
| Layers, outside in | Finish coat, brown coat, scratch coat, metal lath, two layers of building paper, sheathing | Acrylic finish, base coat with mesh, the ICF foam, the concrete | Acrylic finish, base coat with mesh, EPS board, drainage wrap, sheathing |
| Thickness | About 3/4 in. of cement | About 1/8 in. over the foam | About 1/8 in. over 1 to 1.5 in. of board |
| Weight | About 10 lb per sq ft | About 1 lb per sq ft | About 1.5 lb per sq ft |
| Cracking | Will crack; control joints manage where | Hairlines at window corners, rarely more | Hairlines at window corners, plus anything the framing does |
| Where the water goes | Through the cement, down the paper, out the weep screed | Stays out; the foam and concrete are the plane | Behind the board, down the drainage wrap, out the starter track |
| Colour | Paint or a fog coat, every 10 to 15 years | In the finish; fades slowly, recoat at 20 years or so | Same |
| Cold weather | Needs 5 C for days per coat | Needs 5 C for a day or two | Same |
| Where it belongs | Old houses getting matched, masonry walls, people who want the real thing | Every ICF house, which is most of mine | Wood-frame houses with a drainage system, done by a trained crew |
All three rates are supplied and installed with the barrier and flashing allowance their system calls for. None includes bands, frieze or quoins, which are the same price on any of the three and are on the details page.
Cement stucco: the real thing, and the heavy thing
Traditional stucco is a cement plaster. The crew staples two layers of building paper to the sheathing, nails on galvanized metal lath, and trowels on a scratch coat, which they score so the next coat grips, then a brown coat to flatten the wall, then a finish coat with the texture and colour in it. Each coat cures for days before the next, which is why a cement stucco job takes two to three weeks of weather and why the rate is $21 at mid grade. Section 9.28 of the Ontario Building Code is written for this system: the lath, the paper, the thickness, the fastening.
It is strong, it takes a hit from a lawn mower, and it is what you match when you add on to a 1950s house in Toronto or Hamilton. It is also cement, and cement shrinks as it cures, so it cracks. The trade manages that with control joints, metal strips that divide the wall into panels so the cracks happen in the joints instead of across the field. A good crew puts them in at $6 a foot; a bad crew skips them and you get the map of a river delta on your south wall by the third summer. It also wants paint eventually, because the colour is in a thin finish coat that chalks.
Acrylic stucco: the one I use
Acrylic stucco is a different animal with the same name. A cementitious base coat, about 1/16 in., is troweled onto a foam surface with a fibreglass mesh pressed into it, and when that sets a primer and an acrylic finish go over it. The acrylic finish is the colour, all the way through, and it stretches a little, so the small movements that crack cement stucco show up as nothing. The whole system is about 1/8 in. thick and weighs almost nothing, which is why it can go on foam.
On an ICF house the foam is the wall. The crew rasps the EPS face flat, fills any gouges, and starts the base coat. No paper, no lath, no board, no fasteners, and nothing between the stucco and the concrete that can rot. That is the $2 a square foot saving over the same stucco on wood frame, and it is the easiest stucco wall there is; the stucco on ICF page goes through it, and the 2025 finishes-on-ICF guide puts it beside the alternatives.
The weakness of acrylic is that it is thin. A thrown rock, a ladder leaned on it, a weed trimmer at the bottom of the wall, and you have a dent in the foam under a cracked skin, and a patch that never quite matches the texture. Keep stone or a hard base on the bottom 2 ft of a wall where the snowblower lives.
EIFS: acrylic stucco over a board, and the history
EIFS is Exterior Insulation and Finish System: the same acrylic base, mesh and finish, over an EPS insulation board glued or screwed to a wood-frame wall. In the 1980s and 1990s the board went straight onto the sheathing with no drainage behind it, on the theory that the face was sealed and water would never get past it. Water got past it, at every window, every deck ledger and every roof-to-wall step without a kick-out, and it had nowhere to go but into the OSB. The results in North Carolina and in British Columbia made the lawyers rich and the word EIFS poison for about fifteen years.
The system that is sold now is drainage EIFS. A drainage wrap or a trowel-applied membrane goes on the sheathing first, the board has grooves or is set in vertical ribbons of adhesive so water can run down behind it, and a starter track with weep slots at the bottom lets it out. The manufacturers, Dryvit and Durock among them, train and certify the crews and will not warranty a job done by anyone else. Installed by a trained crew with the drainage layer in and the windows flashed into it, it is a good wall at $15 a square foot. Installed by the cheapest guy with a trowel, it is 1995 again. The moisture behind stucco page explains exactly how that goes wrong, and how a drainage plane is supposed to work.
How I would choose
- ICF walls: acrylic stucco directly on the foam, $13 at mid grade. There is no argument to be had.
- New wood-frame house: drainage EIFS from a certified crew at $15, or honestly, fibre cement at $18 if you cannot get the certified crew. The board does add insulation, which the exterior insulation page values.
- Matching an old cement stucco house: cement stucco at $21, with control joints lined up to the originals. Acrylic beside old cement looks like a plastic patch.
- A masonry or block wall: either, with the right primer. Cement is the traditional answer and bonds straight to the block.
- Anything below 5 C: none of them. Book it for May to October and put the +10% winter money toward the bands instead.
Questions people ask
What is the difference between stucco and EIFS?
Traditional stucco is cement over metal lath, about 3/4 in. thick. EIFS is a thin acrylic coating over an insulation board. Both are called stucco by homeowners; they are different walls with different prices, $21 against $15 a square foot at mid grade.
Is EIFS still a problem?
The old face-sealed EIFS from the 1980s and 1990s is, and if you own a house with it, test the sheathing at the window corners. Modern drainage EIFS, with a drainage wrap behind the board and the windows flashed into it, done by a certified crew, is not.
Which stucco cracks less?
Acrylic. The finish is flexible and the base coat has mesh in it. Cement stucco shrinks as it cures and will crack; control joints decide where. On an ICF wall, acrylic stucco has almost nothing moving under it and goes decades with a few hairlines at the window corners.
Does acrylic stucco need painting?
No. The colour is through the finish coat. It fades slowly over twenty years or so and can be recoated with an acrylic finish at that point. Cement stucco wants paint or a fog coat every 10 to 15 years.
Can you put acrylic stucco over old cement stucco?
Yes, if the old stucco is sound and bonded. The crew repairs the cracks, primes, and applies a base coat with mesh and a new finish over the lot. It costs about what a recoat costs plus the base coat, and it is on the repairs page.
Price the one that fits your wall
The exterior cladding cost calculator has all three systems at these rates, with a switch for wood frame or ICF and the details as their own lines. If a quote says “stucco” and does not say which one, the $99 review will find out, and tell you whether the drainage is in it.
Sources and further reading
- Dryvit: EIFS and acrylic finish systems: what a drained EIFS assembly is, the base coat, mesh and finish, and the details at openings.
- Ontario’s Building Code: the official page with the current regulation; cladding is Part 9 Section 9.27, masonry veneer 9.20, attic ventilation 9.19.
- Canada Mortgage and Housing Corporation: the Canadian wall-assembly and moisture research behind rainscreens and the second plane of protection.
