Hello everyone!
Some time ago, we re-poured the slab on the balcony of our house with concrete. Once completed, we hired a roofer to install a 5 mm mat consisting of polyester and bitumen.
They primed the concrete surface with some sort of asphalt primer and later rolled the bitumen mat, heating its underside with a gas burner. They were careful to ensure all seams and edges were sealed, but it is clear the mat has not adhered everywhere in the middle of the floor. You can see bubbles here and there. If you poke them, you can feel that the mat is not attached to the surface in that spot.
It is relevant to add that we had a tiler come by to provide a quote for tiling the balcony. He declined due to the fact that the mat did not seem to be firmly adhered everywhere, and that future condensation from underneath could cause problems with frost bursts, etc., if moisture accumulates between the concrete and the mat.
The roofer, on the other hand, says it doesn't matter if the mat is not 100% glued to the surface, as long as the edges and seams are sealed.
Do any of you wise folks out there have experience with this, and who would it be wise to listen to, the tiler or the roofer?
Many thanks in advance!
Some time ago, we re-poured the slab on the balcony of our house with concrete. Once completed, we hired a roofer to install a 5 mm mat consisting of polyester and bitumen.
They primed the concrete surface with some sort of asphalt primer and later rolled the bitumen mat, heating its underside with a gas burner. They were careful to ensure all seams and edges were sealed, but it is clear the mat has not adhered everywhere in the middle of the floor. You can see bubbles here and there. If you poke them, you can feel that the mat is not attached to the surface in that spot.
It is relevant to add that we had a tiler come by to provide a quote for tiling the balcony. He declined due to the fact that the mat did not seem to be firmly adhered everywhere, and that future condensation from underneath could cause problems with frost bursts, etc., if moisture accumulates between the concrete and the mat.
The roofer, on the other hand, says it doesn't matter if the mat is not 100% glued to the surface, as long as the edges and seams are sealed.
Do any of you wise folks out there have experience with this, and who would it be wise to listen to, the tiler or the roofer?
Many thanks in advance!