Greenhouse floor

[Aves]

I am having a issue with the greenhouse I recently set up. I have placed it over a concrete side walk in my backyard. Now as a new gardener and very first time ever having a greenhouse I wasn't sure of what to put under the greenhouse and if I should be coving the ground it is on. A friend of mine suggested putting a tarp underneath the greenhouse (over the pavement) so that water and bugs couldn't come through the gaps. well it rained heavily today and the floor in the greenhouse has gotten pretty wet. some puddles. Is the tarp underneath a bad idea due to draining? Should I leave the greenhouse directly over the paved sidewalk? Or are there any other ideas on how to prevent water and bugs from coming in through the gaps of pavement and the base of the greenhouse? And also, what should I be doing around the base of the GH? Just so it doesn't flood again!

 

[Susan BBPM]

I'd just put it on the paved area. Typically any patio or paved area is built to drain correctly so putting a greenhouse over the top shouldn't make any difference. In fact, putting a surface on top of the paved area will create a habitat for bugs so is more likely to increase the numbers.

Why does water and bugs bother you? I'm asking this question in case there's something specific you have in mind that I haven't considered. I personally don't see any reason to worry about bugs and water.

What are you growing?

 

[DirtMechanic]

Rubble stone of some small size might be a good idea. That way you can have drainage and be above standing water but bugs and such are kept out. Here we would use something like a crushed limestone so the triangular shapes lock together into a walkable surface. Round stones would never lock and be hard to walk on really.

 

[Oliver Buckle]

The greenhouse that was here when I arrived has a concrete path down the center, but the one I erected has bare earth. I guess it depends what you are using it for. In winter all my non-hardy plants in pots go in there, but come spring I dig out a fair bit of earth and replace it as I grow tomatoes, cucumbers and peppers directly in the soil, and without rotation the soil needs a fair bit of amendment.

 

[brantelyolivia1320]

I am also suffering from the same problem and reach here to get a solution.

 

[Oliver Buckle]

I do wonder what putting it on concrete does from the heat point of view, it is pretty cold stuff, but would it actually warm up and retain heat in a greenhouse?

 

[DirtMechanic]

I do wonder what putting it on concrete does from the heat point of view, it is pretty cold stuff, but would it actually warm up and retain heat in a greenhouse?

The U factor is 75% on a brick, and thickness matters. What comes through, divided into 1 standardizes the R value so 1/.25=R4 on brick.

I see insulation used under cement to enhance the resistance to heat flow and raise the U percentage. Interestingly, denser materials conduct heat better so one trick might be to use foam bead or air entrainment to retard conduction if the floor requirements are not too strenuous. I once was close to a project where concrete was poured for military Abrams tanks to run on and it was to be 9 inches thick. Driveways are at least 4" usually. A 2" concrete pad with re-mesh under a greehouse should be on a firm packed base with thicker edges for wall support, and that gives a chance to run insulation and flexible hot water pipe under the slab for a greenhouse. Thinner might even work but At some point I would add reinforcement fibers to the mix.

Here, the shedding of heat is more important than the retention of heat in a greenhouse. Lots of translucent roof and many just have some spread materials on the floor. A loose material on the floor like bark may well have a surprising insulation equivalent to many materials. Haha- and you can recycle your floor! Further, a greenhouse floor might well be a good use for those fake rubber mulches, especially since they come in colors too!