[argonaut]

I have just bought a 2nd hand greenhouse ...   Eden  Monarch  8 x 10

I am laying a concrete slab this weekend ... and will grow in containers/bags

Just thinking is it worth laying a course of bricks and sitting frame  on bricks ... or save the faff and just sit it on a 2" x  2" treated wood soleplate.

Being on concrete at least wood will not be in contact with ground ... hopefully that means it should last a good few years.

Any other suggestions ?

[Lardman]

Get as much room at the eves as possible, its far easier to do it now than it will be after 12 months. Id go for at least 3 courses especially if you're growing in pots.

Im still musing over brick / block or wooden frame to raise mine this winter.

[Kleftiwallah]

It is stagnant air which allows virus's and other nasties to 'breed', I have mounted my greenhouse on three courses of bricks, the ones with three holes in and the holes are horizontal allowing a good throughflow of fresh air.   Hope this helps?    Cheers,   Tony.

[Nige2Plots]

It is stagnant air which allows virus's and other nasties to 'breed', I have mounted my greenhouse on three courses of bricks, the ones with three holes in and the holes are horizontal allowing a good throughflow of fresh air.   Hope this helps?    Cheers,   Tony.

What a brilliant idea! So simple but very clever!

[mumofstig]

but wouldn't you need some way of stopping cold draughts in the winter 

[Ice]

but wouldn't you need some way of stopping cold draughts in the winter 

That's what I was thinking.

[Nige2Plots]

but wouldn't you need some way of stopping cold draughts in the winter 

That's what I was thinking.

I would bank the holes up with soil!

[Ice]

I would bank the holes up with soil!

Why not just open and close the vents, door or windows?

[mumofstig]

wouldn't beasties get in through the holes as well  mice  :blink:

[ex-cavator]

Not suggesting it would suit everybody, but I've just ripped up a chunk of patio that needed re-doing anyway, and raked over & levelled the sharp sand bed beneath it. I've then covered it with membrane & plonked on it a sturdy greenhouse base constructed from 2 x 4 timber (on edge).

Inside the greenhouse I'll lay a line of slabs up the middle & was toying with the idea of cotswold stone chippings either side on which I can put pots or trays.

Outside I'll spread another inch or so of sharp sand on the membrane & then lay new slabs cut to fit flush to the timber base 

[Paul Plots]

The engineering bricks with holes in as part of a base sounds interesting but, as other people have said, I'd worry about then having to close them off to keep warmth in as well as the host of mickies and other pests that would toddle in. 

I think I am going for a concrete plinth to stand my new lean-too greenhouse on. I do not want to risk using timber as it would rot too quickly. I also want to drill the concrete and anchor the greenhouse down with bolts against fierce winds.

[JayG]

Built mine on a couple of courses of bricks on top of concrete (actually it varies from 1-2 as the existing base sloped in two directions - nightmare!)

The extra headroom is very welcome as I'm quite tall; it's up to you really.

(The bricks were solid concrete ones to keep as many ground-level bugs out as possible, although I did leave a fairly wide empty joint at one corner to make it easier to sweep water out after sluicing down.)

Bed the frame on a layer of frame sealant before bolting or strapping down otherwise you will get annoying leaks coming inside which show up much more with a concrete base.

[Paul Plots]

Thanks for the advice JayG. Last time I put up a lean-to greenhouse it was on the hardstanding along side of our garage. (Not having a car who needs a hardstanding?)

It too was a nightmare as it sloped but, by using shuttering and checking levels, it worked out quite well in the end. A drain-off point is very useful. 

[sazhig]

We'll be sitting our greenhouse on breeze blocks. Much cheaper than bricks 

[JayG]

We'll be sitting our greenhouse on breeze blocks. Much cheaper than bricks 

That's what I intended to use until I realised that they wouldn't work with the sloping concrete base I had to work with (I turned them into supports for my adjustable/removable staging instead!) 

(Make sure you use the heavy concrete blocks rather than the aerated lightweight ones which aren't up to the job.)