Floors for green houses ?

[DragonFish66]

I'm about to order stuff for my new green house in the next few days and was wondering apart from paving slabs what does everyone use for the floor in there green houses ? just weighing up my options

[Phil_SK]

Polythene sheet covered with the heavier, woven plastic type of weed control fabric.

[Apicra]

Paving slabs are good because, apart from providing an internal dry atmosphere, they can be recycled after the greenhouse is no more.

Best wishes,
Derek Tribble.

[DaveW]

I always go for a concrete slab on a polythene damproof membrane being in the building trade before I retired, since I want the greenhouse as dry as possible in winter. Always take time to get the base perfectly level and square since this can make erection of the greenhouse so much easier later. Often better to spend more time on the base than the erection itself.

See:-

http://www.primrose.co.uk/greenhouse-base-help.php

http://www.littlegreenhouse.com/base/base.shtml

These days you can usually hire a mixer quite cheaply and unless you are used to laying concrete in bulk this is the best method since you can work at your own speed, whereas unless it is only a small greenhouse base a ton or so of readymix has to be laid fairly quickly.

I always find it is best to seal any gaps in the greenhouse with sealant as you build it than try and do it afterwards if you find draught or leak.

[Paul in Essex]

Another concrete base fan - easy to keep clean as well as anything else.

Not that I do.

[Benjy]

I've always gone for concrete bases too, even my seperate 'potting shed' gets one

[Aiko]

I have big tiles (paving slabs you probably call them) in use, same we have in use on sidewalks. Easy to put in the greenhouse myself, and you can mess around with water as much as you want, excess water will just run away and in the ground below the greenhouse (unlike a concrete floor, I reckon). Just every now and then I have to rearrange a few tiles that have to carry the heavy tables. An easy job, taking only a few minutes.

[topsy]

Hi,

I would always choose a concrete base, paving slabs still have gaps between them which enables all manner of pests to invade the greenhouse and take bites out of your plants. Weeds cannot come up through concrete, easier to keep clean, you could paint it if you wanted to to give it a better, dust free surface.

Enjoy your new greenhouse.

Suzanne Mace

[Eric Williams]

I agree with Dave W, the concrete slab should have a heavy duty membrane ( as per a domestic floor ) laid underneath. As concrete is porous the membrane will prevent any dampness from beneath. Cheers

[DaveW]

In winter with cacti, you are more bothered with water coming up from below to produce a damp atmosphere than any water you slop around in the greenhouse. A piece of plastic pipe or providing a drain or hole in the slab gets rid of any surplus water. Unless excessive, a wet floor does not matter in the growing season since the sun soon evaporates it through the open vents and the old gardeners used to damp the floors in hot sun to keep the temperature down anyway.

Whether you lay concrete or slabs don't lay them directly on top of garden soil, but remove this top layer and fill with gravel or hardcore, often avaiable from the builders merchant as roadstone (they call it scalpings in the video) topped or "blinded" with sand if needed for a plastic damproof membrane to stop the stones puncturing it.

Preparation for a concrete greenhouse base, or laying concrete slabs is no different to laying the patio in this video, but for a greenhouse or shed unlike being level with the lawn, always make sure your base is a few inches at least above the level of the surrounding garden otherwise you could get back flooding, either up through the slabs or under an aluminium greenhouse sill in very wet weather. The more trouble you take with the base, the less trouble you will have erecting the greenhouse and the more permanent will be the structure.

https://www.youtube.com/watch?v=lvsFCwQNH6w