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NEWSLETTER
from DaveOsborne.com
Volume 7 Issue 4“Building Confidence”April 2009
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Welcome

Welcome to our newsletter. I hope this newsletter will help give you confidence in doing your projects yourself and a question asked by one of our members may be the question you have also.

What's New!

Dan is back from Calgary with certification of the Narconon Drug Rehabilitation Program. Dan is my brother and webmaster of our site. He is branching out to help the drug and alcohol dependents by opening a rehab center. Our best wishes to Dan and his wife Marillyn in their new venture.

Ask Away!

Here are the questions and answers for April:


Dave:
The double layed up cement block chimney on the exterior of our
house, one flue for woodstove and one for oil burner [1986] is now
showing the cement joints throught the parged block. Question is my
best repair plan. Should I erect scaffolding and clean out each of the
joints that are cracking, repoint, then parge whole chimney. Or just
parge the whole chimney?
Rick in Palenville, NY

Hi Rick,

I would fix up the joints in the block, which are structural. These hold up the blocks themselves, as well as the liners. Parging is just for aesthetics, although it may protect the joints from the weather, etc. So point the joints, then parge the surface.

Dave


I pretty much knew that is the right way, the only way but how about the
parging? Is there anything you suggest after I point up. Instead of
reparging the whole thing. Is there anything out there you recommend
like a brush-on product?
Rick

Hi Rick,

I would not recommend a brush-on product, unless this is the way the original was applied. Parging should be about 1/2" thick, made up of cement, sand and a bonding agent. I don't find anything wrong with not doing the entire chimney, except the color difference may vary between the old and new. For only 3 joints it seems alot of extra work to parge the whole chimney, if it doesn't need it.

Is the finish on the blocks a parging or in fact a stucco finish? How thick is it? A stucco is usually 3/4" to 1" thick, made up of 3 layers with the first applied over wire.

I wish I could see a picture of this. Know anyone with a digital camera?

Dave


Dave I'll get a pic to ya in a day or so.....thanks...it is parged, thin
layer right over the block
Rick

Sounds good, Rick.


Dave

Here is a pic, you'll note a repair was made some years ago and
is still holding....
Rick

Hi Rick,

It looks to me that the entire chimney parging should be removed and the concrete block examined very closely. The repair area on the left looks as if it was done superficially, just the parging and not the block. You can rent a small chipping hammer (rotary hammer) and this parging should come off quite easily.

Is the foundation sound or cracked, as well?

Dave


Dave,
Actually most of the parging seems solid. I mean of course I
would chip away at what is loose and has come loose but the whole
chimney, even if it feels and sounds solid?
As for the repointing of the joints do you have any suggestions as
far as adding a hardner or anything like that. Or just mason cement, sand
and lyme and at what ratios do you suggest?
Thanks
Rick

Hi Rick,

If the chimney is solid, no problem, leave it. From the picture it looked like it was all cracked.

Best to get a bag or two of a masonry cement mix from the local hardware or building supply store. Just open the bag and add water. It will say on the bag how much water. You don't need hardener, but you may want to add some acrylic bonding agent along with the water. This helps the cement mix to stick to the block better. Ceramic tile dealers sell this bonding agent. You can add Weldbond to the water, also as a bonding agent. Follow the directions on the bottle. Make sure any dust is removed and you wet the joint with a paint brush, so it is damp, not wet, when pointing the joints and applying parging. Keep the parging damp for 48 hours.

Dave


Dave,

My son came to me with the pictures of peeling paint and concrete
degradation on the foundation of his first home. He was asking
my advice, but I was not sure.
We are wondering why so much concrete is sticking to the paint of
the peeled chip?.
We are also wondering what we can do to remedy this problem.?
Hope you can help?
Steve

Hi Steve,

This is a concrete block wall, right? Three things come to mind:

  1. Has this area ever being close to a fire? Is this a building that was damaged by fire and rebuilt on the same foundation? Fire causes spalling like this.
  2. Is there a possibility of water or moisture seeping down onto the block, freezing and causing the concrete to spall off?
  3. Is the block itself deteriorated to the point that it is structurally defective?

You should really check this one out, below the grade, as well. Concrete block is only about 1 1/2" thick on each side of the hollow web. The top course is usually filled with concrete, though. It won't take too much spalling off like this to occur before the lack of a foundation is putting your son's house in jeopardy.

Dave


Dave,

1. I don't think there was a fire.

2. Water is probably the issue. He gets bubbling under the paint on the
   inside too.

3. The foundation has not deteriorated to a point that it is structurally
   defective. He wants to try and get the moisture stopped.

Do you have any thoughts about the moisture?
Steve

It is hard for me to figure out where the moisture is coming from, not being there. Ideas:

  • plumbing leak
  • blowing rain
  • leaking roof - water leaking down the inside or surface of the wall
  • extreme condensation - not enough air movement
  • bottom of the siding done incorrectly - without a proper drip. Check this out. I looked at your pics again and notice no j-mold on the bottom of the vinyl siding, which is okay if you have a starter strip on the bottom. Make sure there is tarpaper behind the siding and any leaking behind the siding is not continually dripping down onto the concrete block
  • below the grade line - faulty foundation coating and/or drain tile

Maybe refer to this article on vinyl siding: http://daveosborne.com/dave/articles/how-to-install-vinyl-siding.php

Dave


Thanks for the advice.
Last year set a 100 year record for rainfall in his area.
He had the basement and foundation inspected the fall before when he
purchased. It was ruled to be dry. But, with the kind of rain they had,
I thought he was lucky to only get 1/4 inch of water in the basement
one time.
We will check all the items below. Can he do anything to treat the
block and repaint? Or, does he let it dry out good and paint again?
Thanks again

Wow! I thought we had lots of rain here on the West Coast of Canada. What area do you live in?

He should repair the block by scraping any loose concrete and paint off. Then purchase normal Portland cement and sand and mix up a good paste in a wheelbarrow or purchase a product like PolyCement, or a concrete patching mix, depending on the quantity needed.

Personally, I don't paint concrete. Once it is painted it requires maintenance all the time.

Dave


Dave and staff,                         April 18,2009
When I was asked if I could make some type of corner shelves for
statues for St. Marys of the Dunes, I wasn't
sure of a design.
I came across your site and it was, may I say, a Godsend.
I made four of oak sealed with natural Min-Wax and polyurethane.
Thank you for the help. Enclosed are a few pictures.
Sincerely, Thomas, Florence, Oregon

Thanks, Thomas, for the email and pics. Nice job, I'm glad our website was useful to you.

Dave


Hi Dave,

I tell you, I've had nothing but trouble with the caulking around
the tub/tile edge in the bathroom. It seems to turn a foul colour
quickly even though when I remove the old caulk I wipe the area
down with vinegar/water. I'm using a tub-tile caulk (kwik seal)
I keep thinking "am I missing something here?"
Do you have a preferred method in cleaning and re-caulking?
Regards,
Ron

Hi Ron,

You can clean the corner with a Comet cleanser with bleach to kill the mildew. Kwik seal is a latex caulk. You would be better off with a silicon caulk which is mildew resistant. For best results lay down a strip of green masking tape 1/4" from the corner on the tub and on the wall. Then lay the caulking in between, wet your finger and smooth it slightly into the corner. Then remove tape immediately.

Dave

Thanks for the questions and pictures last month. Hope our website is giving you the confidence to do it yourself.

Dave

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