I am going to build a rectangular brick wall 5x4 m (40 cm high) which will be the foundation for a greenhouse. The wall will stand on a newly poured (1 week old) concrete edge beam that is somewhat rough on top. The edge beam is on 15-20 cm of crushed stone 8-16.
I watched the masonry DVD from the craftsman’s school a few months ago and I remember they recommended using a layer of tar paper on the concrete footing before the first course of bricks. Then I've looked at similar masonry where tar paper wasn't used.
Should I lay tar paper under the first course of bricks or not?
/Johan
I watched the masonry DVD from the craftsman’s school a few months ago and I remember they recommended using a layer of tar paper on the concrete footing before the first course of bricks. Then I've looked at similar masonry where tar paper wasn't used.
Should I lay tar paper under the first course of bricks or not?
/Johan
I know nothing about greenhouses, but a brick wall absorbs a lot of water when it rains. It then dries out during dry periods. Additionally, some condensation against the brick can be tolerated at certain times. To divert water accumulated in and on the brick, a step-down in the foundation wall is sometimes performed. Between the brick and concrete, you can place metal, plastic, or paper, which is bent up 50 mm on the inside. This applies to premises with room climate. How a greenhouse should be constructed, I do not know.
Thanks for the answer! I looked in Per Hemgren's "Bygga grund" and underlay felt is also recommended there (but in that case, it was for lightweight concrete blocks on a foundation). Unfortunately, the edge beam is not completely smooth on top, so the felt will lie a bit unevenly, but perhaps it will still be okay.
I understand that the underlay felt is supposed to both prevent moisture from penetrating the brick from below and to function as a sliding layer if there is movement. I'm not sure how this applies to greenhouses.
Is there anyone knowledgeable in masonry who can say how you would approach a similar build, such as an outdoor kitchen/garden wall of brick on a concrete foundation?
/J
I understand that the underlay felt is supposed to both prevent moisture from penetrating the brick from below and to function as a sliding layer if there is movement. I'm not sure how this applies to greenhouses.
Is there anyone knowledgeable in masonry who can say how you would approach a similar build, such as an outdoor kitchen/garden wall of brick on a concrete foundation?
/J