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wet mortar + bonder affect cured Polyurethane Masonry Sealant?

8K views 34 replies 10 participants last post by  dom-mas 
#1 ·
Replacing basement windows in cinder blocks.

This polyurethane based masonry caulk is amazing

http://www.homedepot.com/p/Loctite-...e-Crack-and-Masonry-Sealant-1618522/203156788

so I want to use this as the main sealant and then mortar over it for a nice finish.


Can I brush on a masonry bonder slurry to the cured poly caulk and then mortar (mixed with water plus more bonder) over it and not worry about the bonder/mortar eating away at the poly caulk?
 
#2 ·
Replacing basement windows in cinder blocks.

This polyurethane based masonry caulk is amazing

http://www.homedepot.com/p/Loctite-PL-10-fl-oz-Polyurethane-Concrete-Crack-and-Masonry-Sealant-1618522/203156788

so I want to use this as the main sealant and then mortar over it for a nice finish.

Can I brush on a masonry bonder slurry to the cured poly caulk and then mortar (mixed with water plus more bonder) over it and not worry about the bonder/mortar eating away at the poly caulk?
Shouldn't you ask the manufacture? Im sure there's an 800#. Not being sarcastic or anything. Just saying, that may be the best place for the most accurate info
 
#7 ·
That's how I've always done it, but caulk looks like sh*t as a finish against an existing mortar wash (or whatever you call the angled mortar outside the window that holds in it and keeps water running away). Especially the polyurethane based caulk since it's a lot globbier and harder to smooth to a finish unlike the basic DAP $3 masonry caulk.

The mortar will be applied over about %25 caulk, %25 plastic (the window frame) and the main %50 over the existing mortar, all with bonder slurry added first, and bonder in the water to mix the mortar, so even if mortar doesn't adhere to the caulk, it will to the existing mortar and should to the plastic window frame also, so I'm not worried about it crumbling since it's not as thick of a mortar application VS just mortaring the whole window in without caulking. I added the poly caulk because of it's flexibility from freezing and house settling etc, r value, air and water tight VS just mortar.
 
#8 ·
I am a bit confused...

We have always replaced the windows, hammered and chipped all of the old mortar out, installed new window, foamed and after foam set, mortar winow inplace. We re-create the slope for water to run off and then in the next day or 2, apply clear caulk to mortar and window joint. Minimal caulk and can be completed quickly.

Have I been doing this wrong then?
 
#11 · (Edited)
Did I miss something?

Did the OP say he was installing vinyl windows?

My mistake.

I did miss something. The OP's follow up post.

Set it with minimal expanding foam and some tapcons.

Use the "mortar poly" once the window is set.

"Float" in a sill after the window is set.

(something tells me, I'm still missing something...)
 
#12 · (Edited)
if I do as suggested i.e:
1. great stuff for windows/doors if gap is over about 3/4" after new window is put in. 2. mortar over that and then apply clear caulk where the mortar meets the window once mortar dries,, then what if the house settles or the mortar decides to crack (even with bonder added)? Great stuff (if even needed) isn't waterproof, it's only water resistant. Think of a window 6" off the ground with expanding ice on it for weeks. That's why I think to add sealant/caulk on top of the great stuff (once cured and trimmed) and mortar over everything to complete.
Unless wet mortar eats away at the caulk/sealant, the worst case scenario is that the mortar cracks and a new $3 bag of mortar is needed to repair. I can even go so far as to layer something over the caulk sealant to protect it from the wet mortar.

Caulk/sealant where the mortar meets the windows as the final step is a good suggestion though.


dommas, you contradicted yourself, you told me the mortar will crack as the vinyl and masonry expand but then you told 606 that mortaring is fine.
 
#14 ·
dommas, you contradicted yourself, you told me the mortar will crack as the vinyl and masonry expand but then you told 606 that mortaring is fine.
mortar is fine to fill the space between window frame and surrounding masonry but it WILL crack where it meets the vinyl (or wood or aluminum)...so after the mortar has cured caulk between the mortar and the window. I cut a small key into the joint so the caulk is more than just pasted on

anytime 2 dissimilar [products meet there needs to be an allowance for movement...a soft joint, mortar is the opposite of a soft joint
 
#13 ·
I've never set vinyl windows with mortar acting as exterior trim. I once set windows in a block foundation with stone veneer. I used aluminum capping around the window, with a nice, hemmed bend laying on a flat mortar line to meet the stone.

That was about 9 yrs ago and the job still looks great: no issues.

Glass block, yes.

A picture would help.
 
#17 · (Edited)
ok thanks, so how about instead of caulking where the mortar meets the vinyl after the mortar cures, why don't I put a layer of caulk over the face of the vinyl where mortar will be, let that cure, and then mortar over it so that there's no place mortar touches vinyl. All mortar will meet flexible caulk as illustrated:


do this:






not this:

 
#18 · (Edited)
Vinyl on the window is so slick mortar will not stick. I have splashed mortar on a window without knowing it, came back next day and you can just brush it off. After I mortar, I wait the day or 2 so it dries but the bond also breaks so the window can flex. I do not screw the window in, I foam it in, for those of you that have tried to remove foamed in doors and windows know exactly how it holds.

I had 2 of my guys spend 4 hrs trying to remove a sliding glass door that was only foamed in, it kicked their butts!

There is no mortar around the window, only foam. The mortar then covers the cut flat foam to seal it. Then caulk after mortar is dry
 
#19 ·
You build the second image I posted above but using expanding foam instead of polyurethane sealant. I know great stuff isn't waterproof and is only water-resistant, but maybe you found waterproof foam? I know windows have been set in mortar since like the 1200's or something, but aren't you worried about not having a better sealant like polyurethane caulk or at least non-polyurethane masonry sealant in case the mortar cracks from ice build up (if you live where it's cold)? I'm talking about the main portion of mortar, not just cracking the seam where it meets the vinyl that you say you caulk to allow expansion/contraction.



The windows are already installed and caulked in like the first image 'do this:' minus the mortar yet. I'm waiting back from loctite if their polyurethane masonry sealant will be affected by wet mortar, it probably won't, but if so, it's probably easiest to just caulk over polyurethane caulk with cheaper DAP non-polyurethane sealant:

http://www.homedepot.com/p/DAP-10-1-oz-Watertight-Concrete-Filler-and-Sealant-18096/204167828

because unlike the rubbery polyurethane-based sealant, this can easily be troweled smooth then dusted with mortar to look like mortar. Caulk and walk looks ghetto, I want a nice finish, trim is an option, but kind of tacky and I don't really want to custom cut all the angles and stuff.
Thanks for the suggestions.
 
#25 · (Edited)
Neither picture is correct. Masonry to vinyl or wood or metal is always a soft joint, period.
the 'do this' picture has no masonry to vinyl/wood/metal.

it really seems like you are making something simple into a complicated 4 step process, how big is the gap between the window and the masonry...is the masonry stone or block?
the gap is 1-2" in some places so I great stuff, then polyurethane mason caulk over the great stuff once expanded and trimmed.



mortar is fine to fill the space between window frame and surrounding masonry but it WILL crack where it meets the vinyl (or wood or aluminum)...so after the mortar has cured caulk between the mortar and the window. I cut a small key into the joint so the caulk is more than just pasted on

anytime 2 dissimilar [products meet there needs to be an allowance for movement...a soft joint, mortar is the opposite of a soft joint
yes, my method has no mortar to vinyl contact. Everyone's saying Don't put mortar to vinyl because it will crack, then they say the opposite that they 'mortar and caulk the joint only'. e.g the "not this" illustration. The rest of the mortar on the vinyl besides the caulked joint 'will' crack.

I don't want this to turn into a pissing competition but my method is better for a basic window replacement. It's like $6.50 more in materials per window for polyurethane caulk, but if the house settles, or if the mortar takes a beatin from ice, there's nothing to worry about with high-end sealant underneath.
Even if the mortar doesn't stick to the polyurethane caulk, it doesn't matter, just caulk the joint on top where they meet so ice can't get between the mortar and caulk.


sidenote, if you can find it:

ARCAFLEX FLEXIBLE JOINT MORTAR can be applied on cement, tiling, metal and PVC. Adheres excellently to all building materials
ARCAFLEX FLEXIBLE JOINT MORTAR is ideal for use where increased flexibility and durability are required
ARCAFLEX FLEXIBLE JOINT MORTAR hardens to an elastic waterproofing sealant.


 
#26 ·
your "do this" picture shows mortar as a cove on top of caulking...it won't stick to vinyl but it won't stick to caulking either!!!!!!! Caulking WILL stick to cured mortar but mortar won't stick to caulking. If the joint is 2" wide cap it with aluminum, if you think mortar will look better than that you're nuts.

anyway I'm done...maybe better to have this discussion in the windows and doors section cause you certainly don't like what any of us have to say
 
#27 ·
as noted, the mortar doesn't have to adhere to the cured polyurethane caulk. It probably will anyway especially with slurry bonder, but I can caulk over the seam where the mortar meets the polyurethane caulk, sort of like the 'not this' picture, so ice is less likely to get in between and bust up the mortar. I wouldn't put metal trim on the inside of the window in an unfinished basement.
 
#30 ·
well I heard back from loctite, and they said they don't recommend putting mortar or sealant over the Loctite PL S10 Polyurethane Concrete Crack & Masonry Sealant.
So it's either just caulk, or composite trim after caulk, or caulk then tool and dust with sand that matches existing finish, and/or paint the s10 which it says is okay.
I don't trust mortar not cracking from settling, harsh weather etc.
 
#32 ·
no one but the loctite rep (as recommended to ask by the first reply) said that mortar isn't compatible with loctite np1 masonry sealant - as in that chemically, mortar might degrade the np1.

And just saying, 'Put a sealer over the mortar then and caulk the joint but the mortar should not fail.' If you were referring to NP1 loctite polyurethane masonry, it isn't supposed to go over sealer either.


"mortar is fine to fill the space between window frame and surrounding masonry but it WILL crack where it meets the vinyl (or wood or aluminum)...so after the mortar has cured caulk between the mortar and the window. I cut a small key into the joint so the caulk is more than just pasted on

anytime 2 dissimilar [products meet there needs to be an allowance for movement...a soft joint, mortar is the opposite of a soft joint "

exactly, that why I wanted to np1 everything then mortar over it.
 
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