Hi there,

This year, after many years of threatening, I finally got a greenhouse.

I'm really pleased with it even though I was a bit late (May) to make
full use of it this year but I'm really looking forward to next year and
getting a full load of seedlings on the go. In the past I've had to use
the window sills in the house which limits things and looks untidy.

Anyway I digress. The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold. I used two or three bags of cheapo compost and
spread it on the floor.

Now I'm wondering if there was a better alternative or whether I need to
use anything at all. I intend to use the greenhouse to over winter a
load of our plants which are in terracotta pots and prone to cracking
with the frost. I've got some bubble wrap and will shortly begin to
lining the greenhouse with it. I've also invested in an electric heater
to keep it frost free but also to help get a head start with next years
seeds.

Any advice with the flooring appreciated.

Cheers,

--
Paul Giverin

British Jet Engine Website http://www.britjet.co.uk

In article , Paul Giverin
writes

Anyway I digress. The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold. I used two or three bags of cheapo compost and
spread it on the floor.

Now I'm wondering if there was a better alternative or whether I need to
use anything at all. I intend to use the greenhouse to over winter a
load of our plants which are in terracotta pots and prone to cracking
with the frost. I've got some bubble wrap and will shortly begin to
lining the greenhouse with it. I've also invested in an electric heater
to keep it frost free but also to help get a head start with next years
seeds.

Mine is concrete - easy to sweep clean. I usually raise plants of the
floor in winter by standing them on something (1) balanced on bricks.
The logic of this is that hot air rises so one might expect a layer of
cold air along the floor (2) - in which case, covering the floor with
compost would merely raise the level of the floor and I'd still want to
raise my plants above it. But there's no guarantee my logic is sound.

(1) old pieces of staging, plastic trays, old polystyrene boxes -
anything that comes to hand

(2) and you can sweep under them
--
Kay
"Do not insult the crocodile until you have crossed the river"

In message , Kay
writes
In article , Paul Giverin
writes
Now I'm wondering if there was a better alternative or whether I need to
use anything at all. I intend to use the greenhouse to over winter a
load of our plants which are in terracotta pots and prone to cracking
with the frost. I've got some bubble wrap and will shortly begin to
lining the greenhouse with it. I've also invested in an electric heater
to keep it frost free but also to help get a head start with next years
seeds.

Mine is concrete - easy to sweep clean. I usually raise plants of the
floor in winter by standing them on something (1) balanced on bricks.
The logic of this is that hot air rises so one might expect a layer of
cold air along the floor (2) - in which case, covering the floor with
compost would merely raise the level of the floor and I'd still want to
raise my plants above it. But there's no guarantee my logic is sound.

(1) old pieces of staging, plastic trays, old polystyrene boxes -
anything that comes to hand

(2) and you can sweep under them

Hello again Kay,

Helpful as usual

The mention of polystyrene has given me a thought. I could lay
polystyrene ceiling tiles in the winter when its really cold and I could
lift them in spring when I'm likely to be needing to water stuff inside.
I use those decking squares as duck boards down the middle at the moment
and I could retain these all year round.

Thanks Kay.

--
Paul Giverin

British Jet Engine Website http://www.britjet.co.uk

"Paul Giverin" wrote in message
...
Hi there,

This year, after many years of threatening, I finally got a
greenhouse.

I'm really pleased with it even though I was a bit late (May) to
make
full use of it this year but I'm really looking forward to next year
and
getting a full load of seedlings on the go. In the past I've had to
use
the window sills in the house which limits things and looks untidy.

Anyway I digress. The greenhouse is erected on a concrete plinth
that
was previously used for an aviary. I felt (rightly or wrongly) that
I
needed to do something to insulate the concrete because I though it
would be quite cold. I used two or three bags of cheapo compost and
spread it on the floor.

I can think of no reason why the compost should acquire a higher
temperature than the concrete.

Now I'm wondering if there was a better alternative or whether I
need to
use anything at all. I intend to use the greenhouse to over winter a
load of our plants which are in terracotta pots and prone to
cracking
with the frost. I've got some bubble wrap and will shortly begin to
lining the greenhouse with it. I've also invested in an electric
heater
to keep it frost free but also to help get a head start with next
years
seeds.

Any advice with the flooring appreciated.

The bare concrete will be just fine. Put the compost on the garden
where it will do much good.

Franz

"Paul Giverin" wrote in message
...
In message , Kay
writes
In article , Paul Giverin
writes
Now I'm wondering if there was a better alternative or whether I
need to
use anything at all. I intend to use the greenhouse to over winter
a
load of our plants which are in terracotta pots and prone to
cracking
with the frost. I've got some bubble wrap and will shortly begin
to
lining the greenhouse with it. I've also invested in an electric
heater
to keep it frost free but also to help get a head start with next
years
seeds.

Mine is concrete - easy to sweep clean. I usually raise plants of
the
floor in winter by standing them on something (1) balanced on
bricks.
The logic of this is that hot air rises so one might expect a layer
of
cold air along the floor (2) - in which case, covering the floor
with
compost would merely raise the level of the floor and I'd still
want to
raise my plants above it. But there's no guarantee my logic is
sound.

(1) old pieces of staging, plastic trays, old polystyrene boxes -
anything that comes to hand

(2) and you can sweep under them

Hello again Kay,

Helpful as usual

The mention of polystyrene has given me a thought. I could lay
polystyrene ceiling tiles in the winter when its really cold and I
could
lift them in spring when I'm likely to be needing to water stuff
inside.
I use those decking squares as duck boards down the middle at the
moment
and I could retain these all year round.

That will be an entirely nugatory exercise. Concrete only feels
colder to the feet than a carpet because it conducts heat from the
feet much better than a carpet does. A concrete base for a greenhouse
is about as good as you can get. Be glad you have that possibility.

Franz

"Paul Giverin" wrote in message
...
Hi there,

This year, after many years of threatening, I finally got a greenhouse.

...The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold.

Psst. Carpet tiles.

--
Brian

In message , Brian Watson
writes

"Paul Giverin" wrote in message
...
Hi there,

This year, after many years of threatening, I finally got a greenhouse.

...The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold.

Psst. Carpet tiles.

Thanks Brian. I'd get that leaky bladder looked at though

--
Paul Giverin

British Jet Engine Website http://www.britjet.co.uk

"Paul Giverin" wrote in message
...
In message , Brian Watson
writes

Psst. Carpet tiles.

Thanks Brian. I'd get that leaky bladder looked at though

I'd post a longer reply but .......................

"Brian Watson" wrote in message
...

"Paul Giverin" wrote in message
...
Hi there,

This year, after many years of threatening, I finally got a greenhouse.

...The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold.

Psst. Carpet tiles.
harbour mould spores :0)

"ex WGS Hamm" wrote in message
...

"Brian Watson" wrote in message
...

"Paul Giverin" wrote in message
...
Hi there,

This year, after many years of threatening, I finally got a
greenhouse.

...The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold.

Psst. Carpet tiles.
harbour mould spores :0)

And bare concrete wouldn't?

A hard (ie, not earth) greenhouse floor should remain dry unless watering
the plants on benches or in the side beds splashes over.

Therefore I can't see any problem with carpet tiles which have the benefit
over one piece of carpet of leaving a clean non-fraying, edge when cut.
--
Brian

In article , Paul Giverin
writes

The mention of polystyrene has given me a thought. I could lay
polystyrene ceiling tiles in the winter when its really cold and I could
lift them in spring when I'm likely to be needing to water stuff inside.
I use those decking squares as duck boards down the middle at the moment
and I could retain these all year round.

I think it's unnecessary. Most of your heat loss will be through walls
and top, so thick layer of bubble wrap, as you're proposing, is the best
thing you can do. Ceiling tiles are too fragile to walk on, and you will
want to be in there through the winter to see what is happening, and
clear any dying foliage, and from early spring when you start sowing.

The main cold problem is the cold air outside moving past the greenhouse
- the earth acts as a giant storage heater, so putting an insulating
layer between it and the greenhouse is not necessarily a good idea.
--
Kay
"Do not insult the crocodile until you have crossed the river"

In message , Kay
writes

I think it's unnecessary. Most of your heat loss will be through walls
and top, so thick layer of bubble wrap, as you're proposing, is the best
thing you can do. Ceiling tiles are too fragile to walk on, and you will
want to be in there through the winter to see what is happening, and
clear any dying foliage, and from early spring when you start sowing.

The main cold problem is the cold air outside moving past the greenhouse
- the earth acts as a giant storage heater, so putting an insulating
layer between it and the greenhouse is not necessarily a good idea.

Thanks again Kay. I'll clean out the old compost I give it a try bare.


--
Paul Giverin

British Jet Engine Website http://www.britjet.co.uk

"Brian Watson" wrote in message
...
harbour mould spores :0)

And bare concrete wouldn't?
No because it will dry out whereas carpet tiles if inside a greehouse might
stay damp for ages. Plus you can chuck a bucket of bleachy water down on a
concrete floor or jeyes fluid so killing mould spores and other nasty things
like insect grubs, larvae and eggs.

A hard (ie, not earth) greenhouse floor should remain dry unless watering
the plants on benches or in the side beds splashes over.

Therefore I can't see any problem with carpet tiles which have the benefit
over one piece of carpet of leaving a clean non-fraying, edge when cut.

In message , Brian Watson
writes

"ex WGS Hamm" wrote in message
...

"Brian Watson" wrote in message
...

"Paul Giverin" wrote in message
...
Hi there,

This year, after many years of threatening, I finally got a
greenhouse.

...The greenhouse is erected on a concrete plinth that
was previously used for an aviary. I felt (rightly or wrongly) that I
needed to do something to insulate the concrete because I though it
would be quite cold.

Psst. Carpet tiles.
harbour mould spores :0)

And bare concrete wouldn't?

A hard (ie, not earth) greenhouse floor should remain dry

Oh yeah, hands up those who floor stays dry? :-)


unless watering
the plants on benches or in the side beds splashes over.

1. never heard of 'damping down' - common practice to increase humidity
in hot weather.

2. the OP is going to have pots, presumably on the floor, where do you
think the water will drain out onto?

As others have said it'.s a waste of time with all that glass around
--
Chris French and Helen Johnson, Leeds
urg Suppliers and References FAQ:
http://www.familyfrench.co.uk/garden/urgfaq/index.html

"Chris French and Helen Johnson" wrote
in message ...
In message , Brian Watson
writes

"ex WGS Hamm" wrote in message
...

Psst. Carpet tiles.
harbour mould spores :0)

And bare concrete wouldn't?

A hard (ie, not earth) greenhouse floor should remain dry

Oh yeah, hands up those who floor stays dry? :-)

As far as I can see, there is little difference in potential moisture
retention between carpet tiles and bare concrete because in practice either
option can remain moist enough to retain one sort of "nasty" or another; it
just depends how liberal the user is in their application of water to the
plants.

So, that said, carpet tiles have a slight advantage as the are better
insulators underfoot.

--
Brian