Regrouting my kitchen sink

[Greenman]

That bottom picture looks like termite damage. The brown flakey stuff appears to be termite tubes. Were there any small translucent white bugs in there?

You can't put tar paper in there as it looks like the tile is installed right over the wood. Gluing tile to tar paper won't work. If you want to waterproof the area you'll have to use Red Guard.

 

[Muse]

That bottom picture looks like termite damage. The brown flakey stuff appears to be termite tubes. Were there any small translucent white bugs in there?

You can't put tar paper in there as it looks like the tile is installed right over the wood. Gluing tile to tar paper won't work. If you want to waterproof the area you'll have to use Red Guard.

I have never seen any indication of termite damage anywhere in the house. In the detached (by 20 feet or so) garage, YES! So don't know, I doubt termites. But it's wet, it's dry rot (wet rot!) on top.

Looking closer I see that there are 3 sections of wood at the front. Call them outer, middle and inner, with inner closest to the sink. The outer is 1/2" x 1 3/8" strip that goes all the way across the west cabinet (which has the sink in the middle, standing at the sink, you're facing west), and is likely a solid piece of fir. The middle and inner pieces are 3/4" thick. The middle 3/4" piece extends down 8 3/4" to where the under sink cabinet doors swing out. The inner is 3/4" x 3" and is broken in the middle. I figure I need to remove the inner entirely if possible and replace it somehow. The middle and outer may be OK if I cut away the rot at the top, fill in the removed portion, I suppose with a custom cut strip I glue in. Don't know how far down that rot goes... hopefully not much more than 1/2 inch. I'm surveying and analyzing at this point. Just looked up Red Gard. Gallon is a lot, but maybe has a shelf life once opened, and can use it later.

 

[echo4747]

I have never seen any indication of termite damage anywhere in the house. In the detached (by 20 feet or so) garage, YES! So don't know, I doubt termites. But it's wet, it's dry rot (wet rot!) on top.

Looking closer I see that there are 3 sections of wood at the front. Call them outer, middle and inner, with inner closest to the sink. The outer is 1/2" x 1 3/8" strip that goes all the way across the west cabinet (which has the sink in the middle, standing at the sink, you're facing west), and is likely a solid piece of fir. The middle and inner pieces are 3/4" thick. The middle 3/4" piece extends down 8 3/4" to where the under sink cabinet doors swing out. The inner is 3/4" x 3" and is broken in the middle. I figure I need to remove the inner entirely if possible and replace it somehow. The middle and outer may be OK if I cut away the rot at the top, fill in the removed portion, I suppose with a custom cut strip I glue in. Don't know how far down that rot goes... hopefully not much more than 1/2 inch. I'm surveying and analyzing at this point. Just looked up Red Gard. Gallon is a lot, but maybe has a shelf life once opened, and can use it later.

If you strip off more tiles to the left and right side of the sink... do you think you will run into good (solid) wood?

 

[Muse]

If you strip off more tiles to the left and right side of the sink... do you think you will run into good (solid) wood?

Yes, but I'm not sure I want to strip off any more tiles than I have.

Edit: Pulled off one more front tile on each side. The undersides of the tiles are filled with a cement like substance. Won't be easy to remove that, don't know if I should. Cleaning it, it should stick to whatever... mortar, or adhesive, thinset... ?

 

[echo4747]

Whats is your objective again ...how long do you intend on the repair lasting? Months or years?

 

[Muse]

Whats is your objective again ...how long do you intend on the repair lasting? Months or years?

Oh, years for sure! I think I regrouted this sink in 2005. Caulked too. Haven't done anything with it for 15 years. I'd like this to hold up as much as reasonably possible.

I've got a gallon of Red Gard Regular in my Home Depot cart, not sure if I should get it. I'm confused as to how to do this. Replace rotted wood, then what? I have received two tubes of Loctite 1390595 ADHESIVES_AND_SEALANTS, Single, Tan:

https://www.amazon.com/Loctite-Polyurethane-Construction-Cartridge-1390595/dp/B001E3VQBE/ref=cm_cr_arp_d_product_top?ie=UTF8

That should adhere tiles super solidly to the wood. Seems the thing to do is leave room at the edges to finish off with grout. Would that provide enough protection to the wood from moisture intrusion, though? @Greenman said use Red Gard:

Custom Building Products RedGard 1 Gal. Waterproofing and Crack Prevention Membrane LQWAF1 - The Home Depot

RedGard Waterproofing and Crack Prevention Membrane prevents cracks in tile and stone floors due to surface movement. The membrane also produces a moisture barrier. Suitable for use in residential and

www.homedepot.com

But how would I use Red Gard? It's not really an adhesive, it's a moisture barrier. Use it, then the Loctite adhesive, then the tiles, then grout the edges? Or skip the adhesive? Or skip the Red Gard?

I removed two more tiles, the left most and right most. The wood under the right most removed tile looks pretty good. At the left side, though, the wood's a little punky, not bad, but a little. The right most 2 inches or so (under where the left most tile was removed) is soft to a finger nail, figure removing up to 1/2" would get to solid wood. Tricky to do there, maybe wood chisel work. I have lots of tools including two oscillating tools, but I haven't used one of those yet! I have some epoxy stuff that repairs that kind of thing, I could apply. P.C. Woody, this looks in jars, mine's in cans.

https://www.amazon.com/Protective-Coatings-18434-PC-Woody-Epoxy/dp/B007IBY6H2/ref=sr_1_2?dchild=1&keywords=p.c.+woody&qid=1608231813&sr=8-2

More pics I just took:

 

[echo4747]

if you can cut out all the rot and get back to reasonably solid wood. then piece in some new wood (pressure treated would be nice) You should be able to avoid buying the red guard. Red Gard is a good product but is meant to be applied to a sound substrate. If you use exterior grade construction adhesive to "glue down the ceramic tiles to to some pressure treated wood. It has a pretty good chance of lasting a while eve if a little moisture gets past the the grout between the the tiles.

* you might want to buy a pressure treated deck board and saw/rip it to whatever size you need then screw and glue it in place ( use the same construction adhesive you already have for this)

 

[Greenman]

It didn't look like there was a mortar bed in those first pics, but it's visible in the last ones. You don't need redgaurd. Just a little building paper a little wire mesh, and mortar.

 

[Muse]

It didn't look like there was a mortar bed in those first pics, but it's visible in the last ones. You don't need redgaurd. Just a little building paper a little wire mesh, and mortar.

Could you go into a bit more detail? What's the mortar bed? That's what's on the bottom of the tiles? That's mostly solid, I guess. Is the mortar bed actually tile grout? I see under at least one of the tiles a kind of lattice that's rusted, that would be a sort of wire mesh. I probably have some "building paper" of a sort left over from my garage wall rebuild. I had it under Hardy Board per the manufacturer's specifications. Would that do?

So, staple down some kind of wire mesh over that paper and what? Use that loctite adhesive under the tiles and then grout the sides when the adhesive has set? Or just grout right to the stapled wire mess over paper?

I might have a bit of pressure treated wood left over from the garage repair, maybe not. I can probably rip as needed. I have a homemade electric rip saw I made in the 1970's.

 

[Greenman]

You're on the right track. Repair the rot, staple down building paper (any kind will do) then staple the wire mesh to that. Then you form the top layer with mortar. It's not grout, it's just sand and cement. If you're really going for the pro job you'd through a little fire clay in it and have real fat mud, but that's not necessary. After that dries you reset the tile with thinset mortar. Let that set up for 24 hours then is when you get to use grout.

Wire mesh.

Everbilt 24 in. x 12 in. 18 ga. Plain Expanded Metal Sheet 801417 - The Home Depot

This expanded sheet metal can be altered in shape and cut with proper equipment. Commonly used for small metal repair, duct work, patching, and flashing. Expanded angle comes with several different size

www.homedepot.com

 

[Muse]

You're on the right track. Repair the rot, staple down building paper (any kind will do) then staple the wire mesh to that. Then you form the top layer with mortar. It's not grout, it's just sand and cement. If you're really going for the pro job you'd through a little fire clay in it and have real fat mud, but that's not necessary. After that dries you reset the tile with thinset mortar. Let that set up for 24 hours then is when you get to use grout.

Wire mesh.

Everbilt 24 in. x 12 in. 18 ga. Plain Expanded Metal Sheet 801417 - The Home Depot

This expanded sheet metal can be altered in shape and cut with proper equipment. Commonly used for small metal repair, duct work, patching, and flashing. Expanded angle comes with several different size

www.homedepot.com

So, I need two kinds of mortar? Regular and a thin set? I want to order from Amazon. Home Depot takes weeks now if they ship at all.

I can order what looks like similar metal mesh at Amazon, it looks similar, is actually galvanized too, the Home Depot version is not:

Online Metal Supply Steel Expanded Metal, Galvanized, Flattened Sheet 1/2#16.050" x 12" x 12": Amazon.com: Industrial & Scientific

Online Metal Supply Steel Expanded Metal, Galvanized, Flattened Sheet 1/2#16.050" x 12" x 12": Amazon.com: Industrial & Scientific

www.amazon.com

I also have this 1/2" wire mesh on hand, would it make an adequate substitute?

 

[sdifox]

Yeah it's called kitchen reno.

 

[Muse]

I have some pressure treated wood left over from my garage repair 3 years ago. About 6 foot long, 2 pieces, one a 2x4 the other a 2x6. I think I can probably form a piece that will make up the difference when I cut out the damaged (rotted) wood. Figure I can use the Loctite adhesive to fix it in place, then staple down a piece of the left over tar paper from the garage job, then wire mesh, a coat of mortar, then thin-set mortar the tiles, then grout when the mortar's dry.

The tiles have mortar in the cavities. I figure removing that would be hard if not impossible without breaking the tiles, so I figure clean them up, maybe wash and dry before working with them. One tile's broken in the middle. I guess I could just jam the two halves together, maybe with something between to keep moisture from wicking down, some clear epoxy.

 

[Sgt. York]

Please, lord, don't ever let this thread die.

 

[Greenman]

So, I need two kinds of mortar? Regular and a thin set? I want to order from Amazon. Home Depot takes weeks now if they ship at all.

I can order what looks like similar metal mesh at Amazon, it looks similar, is actually galvanized too, the Home Depot version is not:

Online Metal Supply Steel Expanded Metal, Galvanized, Flattened Sheet 1/2#16.050" x 12" x 12": Amazon.com: Industrial & Scientific

Online Metal Supply Steel Expanded Metal, Galvanized, Flattened Sheet 1/2#16.050" x 12" x 12": Amazon.com: Industrial & Scientific

www.amazon.com

I also have this 1/2" wire mesh on hand, would it make an adequate substitute?View attachment 36015

That mesh will work. Anything is better than nothing.
There are two different types of mortar in that counter top. Regular mortar is just sand and cement, it forms the bed that the tile is adhered to. Thinset mortar is a completely different material. It's an adhesive and that's what holds the tile to the mortar bed.
Look here.
https://tiledoctor.com/countertop-installation-methods/

 

[Greenman]

Please, lord, don't ever let this thread die.

He's just trying to correct the problem on a budget. With a little luck it will get him a few more years of service.

 

[Muse]

That mesh will work. Anything is better than nothing.
There are two different types of mortar in that counter top. Regular mortar is just sand and cement, it forms the bed that the tile is adhered to. Thinset mortar is a completely different material. It's an adhesive and that's what holds the tile to the mortar bed.
Look here.
https://tiledoctor.com/countertop-installation-methods/

I just 15 minutes ago made a Home Depot order, that I'll pickup curbside (hopefully) tomorrow in Emeryville.

I got the wire mesh you linked:

Everbilt 24 in. x 12 in. 18 ga. Plain Expanded Metal Sheet 801417 - The Home Depot

This expanded sheet metal can be altered in shape and cut with proper equipment. Commonly used for small metal repair, duct work, patching, and flashing. Expanded angle comes with several different size

www.homedepot.com

Also, thinset mortar, 1.5lb powdered:

Custom Building Products 1.5 lb. White Tile Repair Mortar-TRMW1 - The Home Depot

Find the Tile Repair Mortar 1.5 lb. Powder Mortar TRMW1, resists mold and mildew fast-setting formula helps you perform same-day grouting at The Home Depot

www.homedepot.com

Reviews indicate it needs more water than the instructions specify, also that it goes off pretty quickly. I may mix more than one batch. One reviewer said mix to consistency of peanut butter. I suppose I'll try that, not rely on the proportions in the instructions.

And what looks like a pretty standard mortar I hope will work fine for a bed between the wood+paper+mesh and the tiles:

SAKRETE 60 lb. Type S Mason Mortar Mix 100033429 - The Home Depot

SAKRETE 60 lb. Type S Masonry Mortar is ideal for patching, bricklaying and stone work. It can also be used as a scratch or brown coat in stucco applications. This premixed mortar reaches a compression

www.homedepot.com

That's probably 50x more mortar than I'll need. Hopefully I can use it for a bunch of bricks that have come loose from my walls and chimney. Seems like it's impossible to buy just a few pounds of dry mortar, say 5 lb.

Info I see online indicates that mortar should have lime, i.e. cement, lime, sand and water. The thinset mortars lack lime, it seems.

 

[Muse]

I'm wondering about my removed tiles (see photos below). Mortar is adhering to the bottoms. It's extending below the bottoms of the tiles. New tiles would be better but don't know if I can find any and the pandemic's going nuts so I don't know that I want to comb the places locally where I might find replacement tiles.

There's what looks like chicken wire embedded in the mortar. Not as bad as something more serious, but adds to the toughness. I'm wondering if I can and should remove some of that mortar, at least to get the excess off so it doesn't extend below the bottom of the 6x2" tiles. How can I remove some of that mortar? I'm afraid if I take a chisel to it, the tile will break.

Notice that the wood piece closest to the sink is now removed. It came off right in my hands when I worked at it a little. The nails that had held it to the outer wood pieces had rusted through.

 

[Muse]

Well, found a short video that shows removing thick mortar from tiles. He doesn't know for sure if the muriatic acid used won't affect the glaze on the front of the tiles, but this appears to solve getting the mortar off the back.

 

[echo4747]

Well, found a short video that shows removing thick mortar from tiles. He doesn't know for sure if the muriatic acid used won't affect the glaze on the front of the tiles, but this appears to solve getting the mortar off the back.

Do you have at least one extra tile that you can use as a guinea pig? You really wont know if it damages the glazing of the tile unless you try it. If you do try this method make sure its outside and wear gloves and safety glasses. It would be a good idea to have a bottle of water with something slightly alkaline that you could use to neutralize the acid should you accidentally get some in your eyes/skin. A pitcher of water with a couple spoonfuls of baking soda would work.

** i'm sure you know to use a plastic pan or bucket and not metal.

 

[Muse]

Do you have at least one extra tile that you can use as a guinea pig? You really wont know if it damages the glazing of the tile unless you try it. If you do try this method make sure its outside and wear gloves and safety glasses. It would be a good idea to have a bottle of water with something slightly alkaline that you could use to neutralize the acid should you accidentally get some in your eyes/skin. A pitcher of water with a couple spoonfuls of baking soda would work.

** i'm sure you know to use a plastic pan or bucket and not metal.

Actually, I didn't know not to use metal pan, thanks. I have many plastic pans I can use. I just ordered a gallon at Home Depot to add to my other order, that's waiting for me at the store. I'd go today but my cell phone's plan expired in Oct. I ordered a new data plan and the SIM's in the mail, but who knows when it will get here, Xmas and all. l could call them and say I'll be there, my car looks like this, license plate is blah blah, I'll be there in 15 minutes. Meantime, I'm still planning. Never used muriatic acid before. Yes, I have at least one extra tile, I have stashed in a drawer, that I can test on.

Klean-Strip Green 1 Gal. Green Muriatic Acid GKGM75006 - The Home Depot

For Pro's and DIY'ers, Klean-Strip is the leading brand of solvents, thinners, removers, and cleaners that are dependable for reliable results. Klean-Strip Muriatic Acid can be used to etch concrete, brighten concrete and masonry, or remove excess mortar from bricks. 90% lower fumes than...

www.homedepot.com

I found a video of a guy working on the backsplash of a sink in a kitchen and it looks uncannily like my kitchen. My kitchen window system is different, but the faucet, the sink and all the tile look exactly the same to me! I'm color blind so the color might be different, but it looks like the same darkish red color to me. You can see the tile color in some of my shots in this thread.

 

[Greenman]

Using acid to break down the mortar is going to leave you with a bunch of hazardous waste. I'd use a grinder with a diamond cutter to remove enough of the mortar to allow you to reset the tile.

As for finding similar tile, it seems extremally unlikely. What you need to do at this point is attempt to produce a serviceable countertop, with the understanding that what you have is at the end of it's life. It's never going to be pretty, your goal is "useable".
Find some tile of whatever color won't be to objectional that also has quarter round trim, and stick it in there in such a way as to make it semi water resistant. With a little luck it will last 4 or 5 years. Start thinking now about how and when you're going to replace those counters. That solution is going to be Formica, as it would be pointless to put anything better on 80 year old boxes.

 

[Muse]

I think I have a diamond wheel for angle grinders that I used on the garage job.

I can use what I have rather than round up substitute tiles, it won't look new but I think it will be serviceable. I think if I do a good enough job with this it can last many years. I haven't picked up the stuff at Home Depot yet, so don't know how thick that wire is. Whatever I do, the level of the tiles has to come out at a certain point, not be off by too much, so that will influence how I go about the repairs. I have to estimate how thick the wood shimming has to be to come out at the right height.

I'm wondering if I should use pressure treated wood. I suppose mortar might not stick to it as well, but the paper barrier and wire on top, I suppose, means that isn't an issue.

I also have wood preservative.

Another thing I have is Quikrete concrete bonding solution, left over from the garage job. I wouldn't want to use that? Say, between the mortar and the thinset? I suppose not.

I figure to put in a piece of wood similar to the one I pulled out exposing the space you see in my last photos. Getting that in place is tricky. I figure maybe a couple of screws temporarily to hold it in place, using that Loctite adhesive. After the adhesive goes off, remove the screws and fill their holes with whatever.

 

[Muse]

Just a cigarette. Ruined a perfectly good smoke.

I've found that pressure for a minute or two usually stops a persistent bleed. Never had a hemorrhage that wouldn't quit.

 

[Muse]

I don't expect easy. Actually, TBH, strikes me as a piece of cake compared to a lot of around the house projects I've faced, managed, and in many cases conquered. No failures come to mind!

I ordered what I think I need, could use, from Amazon, should be here today/tomorrow. Meantime, I'm trying to keep the tile dry in front.

I'm not in a hurry. The wood underneath where those front tiles were has dried out. I'm keeping water off them. I either throw a big towel over the front or just be careful what I'm doing at the sink, so far so good.

I have brought out my as-yet unused oscillating tools, checked out my attachments, even did a test cut in my workroom and am pretty confident I can cut off the rotted top of the wood at the front. Wire mesh should arrive tomorrow. I did a Home Depot curbside pickup on Saturday.

I now have sanded and unsanded grout powders, left over grout additive from years ago I figure is likely still good, a 60lb sack of Sakrete Type S mortar (hope that's a good choice, I really don't know) for under thin-set, a 1.5lb tiny-tub of Custom Building Products modified thin-set mortar powder, a pound of new unsanded grout powder, a pound or so of sanded grout powder for thicker edge seams likely below the 2x6" tiles, a new squeeze tube of white silicone caulking, black paper left over from Hardiboard installation on garage 3 years ago.

Plan at this point is to continue to do research, but ATM, this:

-Cut off the ~5/8" rotted top of wood at front
-Screw and glue down (Loctite tube adhesive) a by-me-custom-cut piece of pressure treated wood on top of the good wood left, dimensions to be determined (!).
-glue in a 3/4" piece of wood close to the sink to replace the piece that just came out in my hands.
-Staple down black paper on the pressure treated wood add-on.
-Staple down pieces of wire mesh on top of that.
-Mortar layer over that using the Sakrete Type S, and level
-Let that mortar layer dry/cure some (HOW LONG I DON'T KNOW!).
-Apply the tiles (which have excess mortar removed from their bottoms somehow... I have muriatic acid and a 4" diamond angle grinder blade, will see what works out) using the modified thin-set.
-Apply grout using additive.
-Seal grout (I have some left from years ago)
-Silicone caulk, newly reinstalled tiles and all around the sink. The caulk elsewhere seems solid, it's discolored, though, figure I can cut away the discolored caulk and replace with fresh silicone.