Subfloor
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Help Support Flooring Forum - DIY & Professional:
Nick
In Remembrance
Sub Floor . Flash the concrete holes . I would have moisture test done .
I had installers do something wrong and tell me they been doing it for year, my response was , you being doing it wrong for all those years.
If you let us know what area you are in , You may be near one of our real Pros.
I had installers do something wrong and tell me they been doing it for year, my response was , you being doing it wrong for all those years.
If you let us know what area you are in , You may be near one of our real Pros.
I am in Toronto. I just received a response from the City Inspector (see below)
I am curious as to why all the holes were being drilled in the basement slab ? Was this to attach a subfloor ?
Why were they drilling all the holes.......could they not have used a different method of attachment or done a "floating" floor ?
As for your questions:
1. - the concrete slab is not really "structural", but drilling all the holes may weaken it's overall strength. This may cause lines of cracking to follow the holes.
This is not necessarily a problem.......slabs can/will crack naturally. Some builders sawcut/ score the concrete so that if it does crack it occurs where the cuts are. It also depends on the diameter of holes.
2. There is a chance water may penetrate slab through holes, but if there is a good deep bed of clear gravel and weepers running into a sump pump this would likely not happen. I think it would only be a problem if water table were high and/ or if water does not drain as described.
3. Yes there is a chance they may have drilled through a pipe.......it depends on how close the pipes are to surface. Hopefully someone had a sketch of pipe rough in locations and they avoided drilling in those locations. However even if they drilled through a pipe it would be in the top and if encased in concrete should not leak.
4. I would have to check what the code says, but I am not aware anything that restricts the drilling of a slab specifically.[/COLOR]
I am curious as to why all the holes were being drilled in the basement slab ? Was this to attach a subfloor ?
Why were they drilling all the holes.......could they not have used a different method of attachment or done a "floating" floor ?
As for your questions:
1. - the concrete slab is not really "structural", but drilling all the holes may weaken it's overall strength. This may cause lines of cracking to follow the holes.
This is not necessarily a problem.......slabs can/will crack naturally. Some builders sawcut/ score the concrete so that if it does crack it occurs where the cuts are. It also depends on the diameter of holes.
2. There is a chance water may penetrate slab through holes, but if there is a good deep bed of clear gravel and weepers running into a sump pump this would likely not happen. I think it would only be a problem if water table were high and/ or if water does not drain as described.
3. Yes there is a chance they may have drilled through a pipe.......it depends on how close the pipes are to surface. Hopefully someone had a sketch of pipe rough in locations and they avoided drilling in those locations. However even if they drilled through a pipe it would be in the top and if encased in concrete should not leak.
4. I would have to check what the code says, but I am not aware anything that restricts the drilling of a slab specifically.[/COLOR]
If all else fail, read the instructions.
http://dricore.com/nw/subfloor_faq.php
Is fastening of the DRIcore Subfloor panels to the concrete floor required?
No, but it is required in some installations. Below is a list of conditions that require fastening:
If a power carpet stretcher will be used to install carpeting: prevent panel uplift when stretching carpet by fastening DRIcore panels to the concrete floor with Tapcon type concrete fasteners at perimeter edges every four feet plus one in the panel in the centre of the room.
(not in the center of every panel)
If using DRIcore panels for a garage or workshop where the panels will be left exposed, fasten every 2nd panel at perimeter wall edges to the concrete floor to prevent lateral movement or shifting with heavy equipment or use. Keep in mind that DRIcore subfloor panels are not manufactured to be a finished floor nor left exposed to exterior weather elements.
In high traffic areas, where the finished flooring material may not be installed, such as hallways.
If installing walls on top of DRIcore: use 2 fasteners for each 8ft base plate, through the panels and into the concrete floor, to fasten base plates.
Call the company and tell them what is happening at your home. They are the only ones that can really help you.
Sounds to me like the installers are re-writing the instructions because they seem to know more than the manufacturer.
Once more, we are just guessing.
Just re read your initial question. You don't have the panels.
If they are installing plywood over the membrane, it would certainly require more fasteners than the Dri-core panel system because a 4x8 sheet of plywood or OSB will most likely not lay flat on the floor. Plywood and OSB are almost always warped to some degree. That's why the Dri-core panel system uses smaller interlocking sections that don't require fastening.
I can see no reason whatsoever to drill all the way through the concrete. It does not add any holding power.
...still, call the company and tell them what you told us.
If they are installing plywood over the membrane, it would certainly require more fasteners than the Dri-core panel system because a 4x8 sheet of plywood or OSB will most likely not lay flat on the floor. Plywood and OSB are almost always warped to some degree. That's why the Dri-core panel system uses smaller interlocking sections that don't require fastening.
I can see no reason whatsoever to drill all the way through the concrete. It does not add any holding power.
...still, call the company and tell them what you told us.
They did not install the Dri-Core. They installed the 5/8" plywood on top of Delta FL dimple roll (they sell this at Lowe's). Their rationale for going all the way down was because they could not get the 2.75" Tapcon screw to go in all the way as there was dust/debris from predrilling. So the geniuses decided to drill all the way through and let it fall from the bottom of the slab.
They could use shop vac with a custom tip and suck out the dust. Or use a compressor and blow air into the holes after drilling.... messy I suppose, but there are ways. One guy blowing the dust out with a second guy holding the shop vac hose close to the hole at the same time.
Did they put a sealer on the screws? That's required. If they did and did a good job doing it, the holes might not be an issue to be concerned about.
City inspector doesn't do flooring and doesn't know why the manufacturer says to use sealer. It's not like water is going to gush up through the holes they drilled. The sealer seals the hole between the screw, hole and membrane which will avoid possible moisture migration over time.......... weeks, months years, ....never? Who knows.
Call the manufacturer on Monday and let us know what they say.
Did you ever have moisture issues in this area before?
I sent my GC the instructions on how to install Tapcon and Delta FL. Both are clear as to how much to pre-drill. In fact, Delta FL says to use 1.5" screws instead of the 2.75" my GC used. He called and asked if I would like to remove the screws and insert epoxy adhesive into the hole and re-screw them back in. I am inclined to remove everything, fill the holes and go with a floating floor at this point. Is there any way to check if any of the PVC pipes have been drilled into?
As far as moisture goes, I pulled some screws out and inserted some thin wooden sticks (shish kabab sticks) and yes they are moist at the bottom.
As far as moisture goes, I pulled some screws out and inserted some thin wooden sticks (shish kabab sticks) and yes they are moist at the bottom.
Maybe if you make sure all your taps are turned off. Take a reading on the water meter by the road, go out for the day then check the readings when you get home This should tell if water is being leaking anywhere
Also something like this might prevent any moisture in the future from holes being drilled through the concrete
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Ok. Actually my water meter is in my basement so I can check fairly easily. But would this also tell me if there are any holes in the sanitary pipes? The Tapcon screws are literally 2" away from these pipes. Do these pipes run vertically down to the footings or can they possibly run under the slab?
How would I go about plugging these holes? What tool allows me to get to the bottom of the slab and at the same time eject some type of epoxy? I don't want to have to make the holes any bigger.
Thanks to all of you for all this help. The guidance and honesty here is truly appreciated.
Thanks to all of you for all this help. The guidance and honesty here is truly appreciated.
I would guess if your water taps are on the outside walls the pipes would not run under the concrete slab eg a kitchen unit in the centre of the room would have pipes under the concrete slab
Sanitary pipes aren't under water pressure
I would think that link I posted would probably work. I have found by using a trowel instead of a roller the Hydrepoxy would be pushed into the drill holes Maybe on second thoughts this might not work as if new holes are drilled the barrier will be compromised again
I maybe overthinking this as I only lay vinyl and live in New Zealand so things and words could be different
The other guys here should add more or better/cheaper ways
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I presume the PVC pipes you are asking about are the ones where water is feed from the road which go through the meter
Waste water could also go through PVC pipes which I don't know how you could check but at least the waste water isn't under pressure
If they had hit pressurized pipes, they would have had water squirting 2 feet in the air.
Pressure testing the drain pipes would mean sealing off all vents and drains............ ie: roof vents, remove and cap the toilet drains and bath tub and sink drains, then pressurize the entire system leaving a pressure gauge in place. If it loses pressure, there is a leak somewhere. Very time consuming and very expensive for someone.
If the contractor saw white or black plastic chips coming up during his drilling process, would he have told you?
I'm gonna guess you have just one drain pipe in the floor and no vent pipes because those go up and out.
I will also assume that the upper level drain pipes all merge into a single basement toilet drain pipe..... meaning that you have only one single PVC drain pipe under the slab.
I also assume that this drain pipe is well beneath the slab since it has to slope downwards beginning at the downstairs toilet flange. I think that drain pipe is buried below the bottom of the slab. Is the sewage pumped up to street level?
You probably have just one water pipe coming into the home. That pipe probably enters the home at the upper level of the home, coming in from the street?
I'm doing a lot of assuming. I'm assuming you have no worries too........unless he used an 8 inch bit.
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I don't know about where you live but the only meter that is on my water line is in my basement There is no need to meter waste water as they figure all the water that goes through the meter also go down the sewer. In my house I have more than one line under my slab but they meet up somewhere under there. House was built in 57 so there is no moisture barrier.
Daris
Daris
