Advice on carpeting an old garage - how to prep old concrete?

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#2927705 15-Jun-2022 09:42

Mine is almost identical in terms of (lack of) level under the door. Other than grinding it down to being all level, the solution I used was mentioned earlier in the thread of gluing a timber strip in behind the door to provide a lip that the door sits in front of.

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tweake

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#2927709 15-Jun-2022 09:50

i would look at grinding/cutting the step back into the door way so the door sits below the floor height.

jonathan18

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#2927711 15-Jun-2022 09:55

geoffwnz:
Mine is almost identical in terms of (lack of) level under the door. Other than grinding it down to being all level, the solution I used was mentioned earlier in the thread of gluing a timber strip in behind the door to provide a lip that the door sits in front of.

Thanks, @geoffwnz, I had a feeling this could be a similar situation to yours. Do you have any type of flooring laid over the concrete?

My concern is that if say carpet is laid to the front of the garage (including under the strip), water may wick further into the garage. I guess this could be solved by starting the carpet behind the strip.

BTW, what sort of sealer did you use to stop water getting under the strip? I guess I just need a decent masonry bit to drill the holes for dynabolts? (How many would you recommend for the length of the strip?) Thanks heaps.

And, yeah, I guess I could look at getting the entrance way ground down so it was even, and that would certainly make sense if I do go ahead and get the professionals in to sort the floor/lay carpet; if I end up doing a DIY I’m not sure if this is worth it…

geoffwnz

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#2927719 15-Jun-2022 10:06

jonathan18:
geoffwnz:

Mine is almost identical in terms of (lack of) level under the door. Other than grinding it down to being all level, the solution I used was mentioned earlier in the thread of gluing a timber strip in behind the door to provide a lip that the door sits in front of.

Thanks, @geoffwnz, I had a feeling this could be a similar situation. Do you have any type of flooring?

My concern is that if say carpet is laid to the front of the garage (including under the strip), water may wick further into the garage. I guess this could be solved by starting the carpet behind the strip.

BTW, what sort of sealer did you use to stop water getting under the strip? I guess I just need a decent masonry bit to drill the holes for dynabolts? (How many would you recommend for the length of the strip?) Thanks heaps.

And, yeah, I guess I could look at getting the entrance way ground down so it was even, and that would certainly make sense if I do go ahead and get the professionals in to sort the floor/lay carpet; if I end up doing a DIY I’m not sure if this is worth it…

There is some carpet at the back of the garage currently. But nothing under the vehicles which can often be muddy (rally car and service ute).

I would lay carpet from behind the timber strip, not under it, for exactly the wicking reasons.

From memory, I used Gorilla Foam of some kind but this apparently is not a permanent solution given the water now seeping under the timber again (though it's not enough to pool like it used to, and it's been a number of years).

I went with 500mm centres on the bolts but that's probably overkill unless you have extremely uneven surface. Then counterbored the timber to leave the nuts recessed/flush so I don't have sticky outy things to catch tyres/toes.

Note, I am not a builder, just your traditional kiwi home handyperson who learns as he goes and googles a lot. :-)

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blackjack17

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#2927720 15-Jun-2022 10:08

jonathan18:
geoffwnz:

Mine is almost identical in terms of (lack of) level under the door. Other than grinding it down to being all level, the solution I used was mentioned earlier in the thread of gluing a timber strip in behind the door to provide a lip that the door sits in front of.

Thanks, @geoffwnz, I had a feeling this could be a similar situation to yours. Do you have any type of flooring laid over the concrete?

My concern is that if say carpet is laid to the front of the garage (including under the strip), water may wick further into the garage. I guess this could be solved by starting the carpet behind the strip.

BTW, what sort of sealer did you use to stop water getting under the strip? I guess I just need a decent masonry bit to drill the holes for dynabolts? (How many would you recommend for the length of the strip?) Thanks heaps.

And, yeah, I guess I could look at getting the entrance way ground down so it was even, and that would certainly make sense if I do go ahead and get the professionals in to sort the floor/lay carpet; if I end up doing a DIY I’m not sure if this is worth it…

I wouldn't bother with Dynabolts.

Use a strip of h3/h4 10mm timber some like this and then put a thick layer of silicon on the base. Secure with some concrete nails

Once secure run a bead of silicon along the front.

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geoffwnz

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#2927777 15-Jun-2022 10:33

blackjack17:

I wouldn't bother with Dynabolts.

Use a strip of h3/h4 10mm timber some like this and then put a thick layer of silicon on the base. Secure with some concrete nails

Once secure run a bead of silicon along the front.

Having found concrete screws for another job, I think I'd use them in future. But since the dynabolts are now in place for mine, I'll re-use them when I reseal it.

Agree that silicone would probably be better than sealing foam.

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MikeAqua

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#2927785 15-Jun-2022 10:51

If this was my house I'd prevent the ingress of water under the door first, and then see how much moisture remains.

If there is still damp, I'd install ventilation and lay outdoor rated carpet. There are outdoor rated carpets now for outdoor dining areas, poolside etc. You could secure the edges with a metal trim profile of some sort if you wanted to.

I don't think you'd be able to resolve the rising damp issue, unless you remove and repour the concrete with plastic film underneath it. Seems like a lot of work/cost for a garage.

Mike

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jonathan18

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#2927793 15-Jun-2022 11:06

MikeAqua:
If this was my house I'd prevent the ingress of water under the door first, and then see how much moisture remains.

If there is still damp, I'd install ventilation and lay outdoor rated carpet.

Yep, this is pretty much my plan. First step is to remove the existing carpet and we’ll get that done this weekend; I’ll need to put polythene or similar under the cupboards to stop them sucking up water from the floor (already happened with one). I’ll also get onto the strip along the door at the same time.

With those two things done I can monitor the floor more easily, and I imagine not having the carpet in place will certainly improve airflow and help dry it out somewhat. I won’t bother putting in carpet (good to know of the ‘outdoor’ stuff, but imagine it’s not cheap?) until we’ve had both a chance to see what happens and to see if we can reduce moisture level around the outside of the garage.

Ventilation is an option, but as you say it’s only a garage. All this work is being pushed by the recent ordering of a new car - I’ve generally not bothered keeping my existing car inside, but this is an EV so it’ll be much easier to charge if it’s in the garage, plus it’ll be brand-new so worth protecting…

blackjack17

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#2927808 15-Jun-2022 11:28

jonathan18:
MikeAqua:

If this was my house I'd prevent the ingress of water under the door first, and then see how much moisture remains.

If there is still damp, I'd install ventilation and lay outdoor rated carpet.

Yep, this is pretty much my plan. First step is to remove the existing carpet and we’ll get that done this weekend; I’ll need to put polythene or similar under the cupboards to stop them sucking up water from the floor (already happened with one). I’ll also get onto the strip along the door at the same time.

With those two things done I can monitor the floor more easily, and I imagine not having the carpet in place will certainly improve airflow and help dry it out somewhat. I won’t bother putting in carpet (good to know of the ‘outdoor’ stuff, but imagine it’s not cheap?) until we’ve had both a chance to see what happens and to see if we can reduce moisture level around the outside of the garage.

Ventilation is an option, but as you say it’s only a garage. All this work is being pushed by the recent ordering of a new car - I’ve generally not bothered keeping my existing car inside, but this is an EV so it’ll be much easier to charge if it’s in the garage, plus it’ll be brand-new so worth protecting…

If you want to stop the moisture and don't really care how it looks under the carpet and want it done cheaply this is what I would do.

Put the timber strip along the front, this will stop water coming in through the front.
Give the concrete a really good clean/acid wash let it dry out.
Put down some plastic waterproof membrane glue it in place so it doesn't move around (or paint with crystal proof or both).
Put down some garage/outdoor carpet/marine carpet like this or this and put a timber strip secured the same way as under the door around the outside to hold everything in place.

Will look much better, won't rot and should last a while. If you are putting wooden cabinets in, place on plastic or elevate above the carpet incase water does get in.

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jonathan18

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#2927827 15-Jun-2022 11:46

Good ideas; I think it’ll make sense to clean the the concrete before putting down the timber strip, though. What’s a recommended cleaning product to use? Is it sensible to use a waterblaster as well? (The garage will be totally empty; I think the walls will cope ok with being washed down to get rid of any splashed crud.)

Looking into acid wash, I’m taking that would be in preparation for placing down a membrane or waterproofer - do I need to do that at this stage, or do it if we decide to go ahead to waterproof and carpet?

Thanks again for the really useful advice.

Jase2985

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#2927829 15-Jun-2022 11:47

i got one of these for my old garage, Raven RP4, comes with a threshold seal and a seal for the bottom of the door.

https://www.raven.com.au/domino/raven/ravenweb.nsf/prod2-v/023

I used concrete screws and silicone to stick it down and it worked great

jonathan18

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#2942062 15-Jul-2022 08:55

Given the recent weather, we haven't got the garage floor sorted yet! But have decided to do a DIY job that should cost a 1/3rd of getting the professionals in and, while it may not last forever, it'll be a lot better than what it has been. (Also, builder colleague reckons there's a soak pit in the lawn right next to the garage which is needing cleaning out; along with adding drainage in the lawn leading to the soak pit this should reduce moisture level here.)

Anyway, today I'm going to grab the wood to put behind the garage door to reduce rain egress, but just wanted to confirm the best height for this: the gap on the far right in the photo below is a significant 3cm (to the metal of the door; less to the rubber seal). Obviously I don't want to put a 30mm chunk of wood as that's going to be a pretty major tripping hazard, but would 15mm (or even the 10mm suggested earlier) be adequate? (ie, do I need to completely block the gap, or will it work simply providing a lip to stop water flowing under?)

Thanks again...

geoffwnz

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#2942070 15-Jul-2022 09:12

Mine is (measured) 23mm decking timber. Have never had any issues tripping on it and the cars have no issue driving over it.

It'll prevent flowing water coming under the door but if there's still a gap to the door at one end you'll still get some blown water in certain weather.

Mine is remarkably similar (what are you doing in my garage? ;-) ) in the mess of slopes and crap concrete. The gap at one end of mine is just within the 25ish mm of the timber strip so prevents 99% of blown water.

My next project along with reapplying sealant under the boards will be to take a concrete grinder to the entrance and level it off so the door can sit evenly across it's length. That may require lowering the tracks on each side slightly so the holes for the catch still line up rather than enlarging the holes and having the door able to be lifted possibly 50mm.

I am also getting a strong temptation to cut out the floor in sections and replace the concrete properly with a moisture barrier under it, potentially raising the entire floor by 25mm to provide that lip for the doors. I'd leave a lip round the edges (width to be determined) so I'm not undercutting the wall footings and also gives me something to run the screed on.

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jonathan18

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#2942074 15-Jul-2022 09:22

geoffwnz:

Mine is (measured) 23mm decking timber. Have never had any issues tripping on it and the cars have no issue driving over it.

It'll prevent flowing water coming under the door but if there's still a gap to the door at one end you'll still get some blown water in certain weather.

Mine is remarkably similar (what are you doing in my garage? ;-) ) in the mess of slopes and crap concrete. The gap at one end of mine is just within the 25ish mm of the timber strip so prevents 99% of blown water.

My next project along with reapplying sealant under the boards will be to take a concrete grinder to the entrance and level it off so the door can sit evenly across it's length. That may require lowering the tracks on each side slightly so the holes for the catch still line up rather than enlarging the holes and having the door able to be lifted possibly 50mm.

I am also getting a strong temptation to cut out the floor in sections and replace the concrete properly with a moisture barrier under it, potentially raising the entire floor by 25mm to provide that lip for the doors. I'd leave a lip round the edges (width to be determined) so I'm not undercutting the wall footings and also gives me something to run the screed on.

Sweeet! Re decking timber - did you put the grooves up or down? I think 23mm will work fine (noting you say tripping isn't an issue - but you may not have people like my wife and son, who can trip up on a totally flat surface!), as there's still the rubber seal that'll minimise the gap.

The floor is starting to look better already - it's dried out a decent amount (left doors open for a couple of weeks with the garage fully empty), I've filled the big hole showing in the middle (would have been where the original doors fastened in the middle), and have filled in the cracks. I also cleared away any soil and roots from along the side. Next week it's sealing the concrete then we'll lay the carpet ourselves the following week - not sure whether to tape it down or not (previous one was just 'floating' but never moved; I'm thinking, though, that taping at the front in particular may minise movement from contact with the car wheels, which is where it wore so badly the first time).

I'm happy to pause all the above if you'd like to come and test your own plans out first on my garage?!

geoffwnz

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#2942077 15-Jul-2022 09:32

jonathan18:

geoffwnz:

Mine is (measured) 23mm decking timber. Have never had any issues tripping on it and the cars have no issue driving over it.

It'll prevent flowing water coming under the door but if there's still a gap to the door at one end you'll still get some blown water in certain weather.

Mine is remarkably similar (what are you doing in my garage? ;-) ) in the mess of slopes and crap concrete. The gap at one end of mine is just within the 25ish mm of the timber strip so prevents 99% of blown water.

My next project along with reapplying sealant under the boards will be to take a concrete grinder to the entrance and level it off so the door can sit evenly across it's length. That may require lowering the tracks on each side slightly so the holes for the catch still line up rather than enlarging the holes and having the door able to be lifted possibly 50mm.

I am also getting a strong temptation to cut out the floor in sections and replace the concrete properly with a moisture barrier under it, potentially raising the entire floor by 25mm to provide that lip for the doors. I'd leave a lip round the edges (width to be determined) so I'm not undercutting the wall footings and also gives me something to run the screed on.

Sweeet! Re decking timber - did you put the grooves up or down? I think 23mm will work fine (noting you say tripping isn't an issue - but you may not have people like my wife and son, who can trip up on a totally flat surface!), as there's still the rubber seal that'll minimise the gap.

The floor is starting to look better already - it's dried out a decent amount (left doors open for a couple of weeks with the garage fully empty), I've filled the big hole showing in the middle (would have been where the original doors fastened in the middle), and have filled in the cracks. I also cleared away any soil and roots from along the side. Next week it's sealing the concrete then we'll lay the carpet ourselves the following week - not sure whether to tape it down or not (previous one was just 'floating' but never moved; I'm thinking, though, that taping at the front in particular may minise movement from contact with the car wheels, which is where it wore so badly the first time).

I'm happy to pause all the above if you'd like to come and test your own plans out first on my garage?!

Nice try. :-P

There's no grooves showing on mine, so I guess they are down. Also for mine, it's not a main foot route as I have a back door on the garage that's next to the main house entrance.

The difference in water in flow when I first put mine in was amazing. Went from lakes every rain to basically dry. With the amount of water in the ground from the recent rain volume the concrete is damp in places except for where I've already relaid it (old work pit and a couple of patches that had basically turned to gravel) despite not using any form of moisture barrier under them.

As for securing the carpet, one option is to try it floating and see if it moves. Another option could be to sandwich it under the timber entrance strip but I am thinking this may not be so useful as it might end up sucking moisture under the strip and/or prevent it from sealing to the ground properly. Could just staple a 10-20mm overlap to the top of the timber strips potentially.

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