New answers tagged concrete
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Stained concrete
Based on your description it's highly unlikely that the sticky stain was caused by your fiber mat or defective concrete.
Without knowing the cause, it's difficult to recommend a specific solution. You ...
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Concrete/ cement screws for dry wall?
So, it's difficult to understand exactly what you're asking--are you are asking "What is stronger than a drywall screw for hanging heavy things like pictures or fire extinguisher brackets?"
...
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Waterproofing concrete wall
Tile sets well on block walls. There is not a requirement to cover with cement board, but if you feel you must, add firring strips and then the cement board.
I have used the Aquadefense on many ...
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Accepted
What's this grey stuff on concrete wall
Dirt, mold, mildew and/or algae.
Wash it, bleach it, possibly pressure-wash it with likely paint removal as a result.
Repaint it once dry with suitable masonry primer and paint for exterior use.
- 200k
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How to repair the caulking around basement walkout doors and what to use?
I would avoid using a flashing/drip edge type of solution unless it was cemented down to the concrete somehow with no loose edges. You don’t want to have something to catch your foot on, especially ...
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Avoid rust where railing anchors into concrete
Bolt the posts onto the concrete floor (raised locally by a grout top) with an insulating mica sheet placed between the post flange. The anchor bolts to have an insulating washer between the flange ...
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Installing door in a basement window to make a basement walkout
The problem is if that wall on top of part of the foundation is a support wall. This can happen if either the roof, or any of the floors above that point have joists/trusses that run perpendicular to ...
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How do I calculate the concrete needed for a fence post?
rule of thumb is post hole is twice the size of post being used 1 bag of concrete 60#or80# will be fine placed at the bottom of post hole allow 6or8 inches below top of ground for dirt or gravel ...
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In a house fire, how hot does the foundation have to get before it too has to be replaced?
Hmm, I am a structural engineer and suffered a total loss house fire in 2015. The house was wood. I felt that most heat went up and that the concrete in the footings would be somewhat unaffected. I ...
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How do I fix the gap between my driveway and floor?
Expansive soil grows with water, so preventing water from percolating down the expansion joint should prevent further damage. Removing the expansion joint material and caulking the joint sounds like a ...
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Why is my neighbor's A/C causing my walls to sweat?
This plan seems to assume that water is coming through the wall from the neighbor's side to yours.
If the problem is caused by temperature-based condensation, this has no hope of working, because the ...
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Why is my neighbor's A/C causing my walls to sweat?
A much simpler solution here would be to add thermal insulation to minimize the heat transfer pulling your side to below the dew point.
None of what that contractor is proposing is adding thermal ...
- 11.5k
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Which wire and conduit with already-present outlets in the basement
Romex sleeved in conduit for physical protection is FINE. But annoying when already installed, as you have to disconnect, sleeve and reconnect, which is a pain, doubly so if you are not entirely comfy ...
- 200k
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Running 14/2 Romex vertically up a concrete wall
Most LAHJs consider it exposed to damage, so some form of protection is required.
That could be schedule 80 PVC conduit. It does not need to be metal. That could be a board. Typically it needs to ...
- 200k
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What happens if I paint a concrete floor without pre-treating it?
It's 2023 now and I painted this floor in 2016. I figured I could post a photo of the floor from this year, when I cleaned out most of my woodworking machinery to move it to another building. The ...
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Anchoring aluminum pergola to 4" slab
Replace the shipped concrete screws with screws of equal or greater diameter and equal or greater length.
How big of a deal the anchors are depends on what they're doing. If your pergola uses moment ...
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Accepted
Anchoring aluminum pergola to 4" slab
You need to drill at least 1/2" deeper than the screw. Concrete debris accumulates in the hole quickly and would prevent full penetration of the screw. All that's in the instructions, though:
...
- 129k
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Do I need to remove mold stains before applying foundation waterproofer?
Any cold surface will always act as a duhumidifier. If you have dust on that surface you have food and water which is perfect for mold.
Before you do anything with is your RH in the area?
It seems ...
- 13.4k
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How can I fasten wooden stair treads to porcelain tile on concrete?
IRC R311.7.5.1 specifies that the difference between the largest and smallest riser in a flight of stairs shall be 3/8" (9.5mm) or less. If your applicable code isn't based on that, it still very ...
- 200k
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How can I fasten wooden stair treads to porcelain tile on concrete?
Heavy duty construction adhesive will do the job, assuming that the tile is all well bonded. Use a 3/8" (8mm) bead in a zigzag or grid pattern and hit the perimeter well.
I'd be concerned about ...
- 129k
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Reinforcing concrete wall of outdoor hot tub?
Your hot tub surcharge on the pool's retaining wall may be moving the wall. In this scenario the sinking hot tub has been caused by soil settlement, and that soil settlement has been caused by the ...
- 5,144
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ICF home -- are columns in the photos load bearing?
Assuming that the rectangular box above the sliding doors is HVAC duct feeding an upper story, then yes those columns are load bearing. The ceiling joists run perpendicular to that HVAC duct. That's ...
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ICF home -- are columns in the photos load bearing?
Caveat: Amateur rather than professional here.
I am almost certain these are load-bearing. Tell-tale signs for me:
Columns which are this thick (or rather, with minimum dimension this big) - some of ...
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ICF home -- are columns in the photos load bearing?
In a concrete wall (which is what an ICF house is built from) those are certainly load-bearing concrete columns. It would have required some very deliberate design to make the header over that space ...
- 200k
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How can I construct an outdoor concrete pad and retaining wall that will also work as a basement floor and foundation wall?
I don't see changes to IRC R403.3 in the amendments of Massachusetts, so R403.3 would be your shallow foundation detail. Because of that 64 degree mean temperature constraint, I don't think that a ...
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Concrete Control Cuts
His tool probably couldn't reach all the way to the house.
Your concrete is going to crack regardless of how many control joints there are. The control joints are analogous to electrical fuses, where ...
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How do I go about repairing/redoing this uneven and damaged basement concrete floor?
The good news is that you do not necessarily have to worry too much about future cracks in the concrete because I strongly recommend that you cover your floor with a tiny bit of wood. Nothing fancy, ...
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How do I go about repairing/redoing this uneven and damaged basement concrete floor?
Any half hearted attempt to "repair" the floor will eventually end up cracked again, in all the same spots as they move independently from one another. The only real chance would be to cut ...
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How do I go about repairing/redoing this uneven and damaged basement concrete floor?
The best solution would be to break it all up and re-pour a nice monolithic reinforced slab. That's also expensive and a lot of work, so you might want to consider attempting "not the best" ...
- 200k
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Accepted
How to mount cabinets on concrete wall
When you mount things on wood (plywood over concrete/brick/block/etc. or into studs):
You can remove and replace easily. If you want to replace in the exact same spot, use a slightly larger screw ...
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How to shorten a concrete pipe sticking from ground
My answer assumes your local ordinance permits you to achieve your goal.
Mark the inside perimeter with a sharpie or paint line for guidance
Use a masonry bit to drill a few holes next to each other ...
- 16.5k
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How to shorten a concrete pipe sticking from ground
Obviously, with a cutting wheel, you would cut around the outside, as deep as possible. 6cm, you say. That will cut through at least some of the concrete wall. Don't forget to stuff a cushion or ...
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Accepted
How to shorten a concrete pipe sticking from ground
There exist dedicated concrete cutters. For example the Stihl TS 420 has about 12cm cutting depth. I don't know if those saws allow horizontal cutting.
A preferred solution would be to simply raise ...
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