Last year, I decided to install decking on an existing concrete floor, which also serves as the roof for part of my garage located in the basement. The solution then was to drill and plug for each decking screw. I also had to prop it up so that it would be even with the patio and stairs, as there is a slight slope on the concrete slab.
The result was not good. The decking became "wavy" because I had propped it up, which resulted in a slope towards the facade where water collects. I also set the decking too closely together so that the water couldn't pass through, and the propping wood I placed under the decking blocked the water from draining off the slab, as it was aligned with the house.
In the winter, I discovered that water started dripping into the garage under the concrete slab. I suspect that one of the holes is allowing water to enter… from what I understand, there is a hole near the patio door.
So now to my questions:
1. How do I seal this? Seal each hole? Use tar paper? Putty?
2. What is the best way to handle the new decking? I have the option to place a "joist" under the decking that builds up to a max of 28mm. However, due to the slab sloping outward, the new decking will protrude 28mm and not at all at the edge of the slab. The plan is also to lay the decking in the other direction, so that the joists underneath run away from the house.
If you have any questions, feel free to ask them.
The result was not good. The decking became "wavy" because I had propped it up, which resulted in a slope towards the facade where water collects. I also set the decking too closely together so that the water couldn't pass through, and the propping wood I placed under the decking blocked the water from draining off the slab, as it was aligned with the house.
In the winter, I discovered that water started dripping into the garage under the concrete slab. I suspect that one of the holes is allowing water to enter… from what I understand, there is a hole near the patio door.
So now to my questions:
1. How do I seal this? Seal each hole? Use tar paper? Putty?
2. What is the best way to handle the new decking? I have the option to place a "joist" under the decking that builds up to a max of 28mm. However, due to the slab sloping outward, the new decking will protrude 28mm and not at all at the edge of the slab. The plan is also to lay the decking in the other direction, so that the joists underneath run away from the house.
If you have any questions, feel free to ask them.
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Seal with sluring (thin cement mixture) or another cement-based product for the purpose. For example, this one: https://www.bauhaus.se/cement-expre...YcHLy_aztRGUGtU4ErtxowIFGkN8-qghoC3uUQAvD_BwE
Thiger said:
Awesome, will try this, bought a tube yesterday!
