To anyone with advice-
My husband and I turned a concrete block warehouse into our home. We are now ready to finish the outside and want to use a dyed stucco finish. The block was laid horribly and the mortar joints are oozing with mortar up to 1/4″. We finished the inside walls with studs, insulation, a vapor barrier, then drywall. We opened one of the walls to find the insulation was a bit damp I assume from condensation. I’m wondering if we shouldn’t have placed the vapor barrier against the block, then the studs and drywall but too late now. We are wondering if we should cover the outside block with insulation board, lath? and then stucco to help insulate the block more and smooth out the finish or just parge the house heavily with portland cement and a finish coat of Fibercoat or similar product. Cost of course is somewhat of an issue too. Does anyone have any thoughts/ advice? Our house has 12′ first floor ceilings and 8′ second floor so it is very tall.
Replies
> The block was laid horribly and the mortar joints are oozing with mortar up to 1/4".
This is a good thing for your project. It gives the stucco something to grab. Put on some of that PVA bonding agent, and stucco right over it all.
> I'm wondering if we shouldn't have placed the vapor barrier against the block, then the studs and drywall but too late now.
Oy, yes. That's where you should have stopped the water. You might look at http://www.xypex.com, mix it in your stucco. It'll stop water from soaking thru, but it won't help if condensation is the problem.
-- J.S.
John Sprung- thank you for your input. I suppose you think we should not put insulation board on at all. We were thinking it might insulate the block better to prevent the condensation could be happening. Also, the block on our house is painted but it is very flat paint. Its not glossy like semigloss. Do you think we need to sandblast it if we don't use the insulation board or is the PVA bonding agent good enough? Where do we get this PVA stuff?
Given that the block is painted, the board sounds like a better idea. To stucco directly, you'd have to sandblast to get a reliable bond, and that's messy and expensive. If you're going to go to the work of attaching something to the outside of the block wall, perhaps consider Hardie board or something that gives you a final surface without the additional step of stuccoing. PVA and stucco mix can probably be found at a box store, but for the volume you'd need, look for a masonry supply house if you still decide to go that way.
-- J.S.
There are several products on the market for commercial finishes ...which is what you are dealing with , but on a smaller scale. Drivet makes a stucco finish that can be applied directly , as well as with the foam insul board...this gives you a water proof finish with several types of textures...Ask your commercial drywall supply house for a few contractor products that might be available, they usually supply drivet or a effis type product.... As far as the hind sight on the interior walls,....good luck, Mark Rogers, G.C. #643905
Thanks for the advice. I am not particularly fond of dryvit products but perhaps I shouldn't totally write it off. We were hoping to use cement stucco.