A word of warning and a question.

I was given a greenhouse this year. I duly laid a rectangle of concrete
(just the outline, not a complete slab) and built the greenhouse on top.
The greenhouse itself has a rolled steel base and the aluminium frame is
clipped to this steel base. Note that the steel based is NOT fixed to the
concrete - it just rests on it.

OK, you've guessed it; the entire greenhouse slipped 6 inches sideways this
weekend in the gales. Remarkably, no broken glass. That's the warning for
those planning to build a greenhouse - "bolt" it down.

Now the question - how? My concrete is about 4inches x 4inches on a
hardcore base (sunken into the ground) so won't take rawlbolts. I'm
considering a piece of dexion hammered into the ground in each internal
corner and then bolting this to the steel base. Do the readers think I need
to concrete the dexion in as well or would 2ft long pieces sunk into the
ground be enough?

The greenhouse is about 8ft x 6ft and presents the 8ft side to the wind.

Thanks for any advice.
Paul DS.

--
Please remove the "x-" if replying to sender.

"Paul D.Smith" wrote

OK, you've guessed it; the entire greenhouse slipped 6 inches sideways
this
weekend in the gales. Remarkably, no broken glass.

Well... Concidering the laws off phisycs the first is most probably the
cause off the second, the force off the wind was demped by the movement. If
it would be fixed the pressure on the glass would be more intens, and the
glass would have broken.

Marc (but unfortunately I know litle about gardening)

Well yes but... I would have personally placed my money on the entire frame
flexing sufficiently to crack a pane or two. That it didn't is testament to
the rigidity of the frame and glass plus the adhesive qualities of the glass
beading that is between the frame and glass. Any "looseness" in the
structure and one or more sides could have flexed and the glass would have
cracked.

Paul DS.

In message , Paul
D.Smith writes
OK, you've guessed it; the entire greenhouse slipped 6 inches sideways this
weekend in the gales. Remarkably, no broken glass. That's the warning for
those planning to build a greenhouse - "bolt" it down.

Now the question - how? My concrete is about 4inches x 4inches

A very small greenhouse.........
on a
hardcore base (sunken into the ground) so won't take rawlbolts.

Why not? An SDS drill should drill holes in that without any great
problem

I'm
considering a piece of dexion hammered into the ground in each internal
corner and then bolting this to the steel base.

Sounds OK in principle.

Do the readers think I need
to concrete the dexion in as well or would 2ft long pieces sunk into the
ground be enough?


I would think that a hammered into the ground would be fine in terms of
holding firm. Though you will need to get it in exactly the right place
to fix the GH to, not always easy when hammering in (and the top will
get a bit bent as well probably).

I would concrete shorter lengths in.

Put the GH in the correct place if necessary. Dig the holes, bolt the
Dexion to the GH with the Dexion in the holes, then put the concrete
around the Dexion.

I bolted length of treated timber to the blockwork base of ours and then
fixed the GH frame to the timber.
--
Chris French and Helen Johnson, Leeds
urg Suppliers and References FAQ:
http://www.familyfrench.co.uk/garden/urgfaq/index.html

'Twas Mon, 28 Oct 2002 08:44:51 -0000, when "Paul D.Smith"
enriched all our lives with these worthy
thoughts:

Now the question - how? My concrete is about 4inches x 4inches on a
hardcore base (sunken into the ground) so won't take rawlbolts.

Why not? You can get 50mm anchor bolts from most BMs for about
50p each.

I'm
considering a piece of dexion hammered into the ground in each internal
corner and then bolting this to the steel base. Do the readers think I need
to concrete the dexion in as well or would 2ft long pieces sunk into the
ground be enough?

Why not fix a length of, say 50x100 treated timber to the base
and then fasten the GH to the timber. It would give you an extra 50mm
head clearance.

--
cormaic URG faqs/webring - www.tmac.clara.co.uk/urgring/
Culcheth Garden - www.tmac.clara.co.uk/garden/
Warrington Paving - www.pavingexpert.com/
Peoples' Republic of South Lancashire

cormaic CAN BE FOUND AT borlochshall.co.uk

Both yourself and The French's suggested anchor bolts.

Correct me if I'm wrong, but I thought these were like metal rawlplugs in
that they expand in the holes. At only 4inches wide, I would not expect the
concrete to have enough torsional strength to hold them in place. In short,
I would expect to tighten the bolts and have the anchor bolts split the
concrete into two chunks.

If anchor bolts are something else, please fill me in on how they work.

Thanks,
Paul DS.

Paul D.Smith wrote:
Both yourself and The French's suggested anchor bolts.

Correct me if I'm wrong, but I thought these were like metal rawlplugs in
that they expand in the holes. At only 4inches wide, I would not expect the
concrete to have enough torsional strength to hold them in place. In short,
I would expect to tighten the bolts and have the anchor bolts split the
concrete into two chunks.

If anchor bolts are something else, please fill me in on how they work.

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

--
Grunff

'Twas Mon, 28 Oct 2002 16:48:52 +0000, when Grunff
enriched all our lives with these worthy thoughts:

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

4" *wide*??? I assumed that was an error and the OP meant 4"
*thick*. At 4" wide, it's doing well holding itself together!

In that case, I'd use frame fixings to fasten a timber batten
to the concrete and then fix the GH to the battens. If the frame
fixings are at, say 500mm centres, that should be adequate to anchor
the battens and the GH.

--
cormaic URG faqs/webring - www.tmac.clara.co.uk/urgring/
Culcheth Garden - www.tmac.clara.co.uk/garden/
Warrington Paving - www.pavingexpert.com/
Peoples' Republic of South Lancashire

cormaic CAN BE FOUND AT borlochshall.co.uk

In message , cormaic
writes
'Twas Mon, 28 Oct 2002 16:48:52 +0000, when Grunff
enriched all our lives with these worthy thoughts:

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

4" *wide*??? I assumed that was an error and the OP meant 4"
*thick*. At 4" wide, it's doing well holding itself together!

I thought something similar.

In that case, I'd use frame fixings to fasten a timber batten
to the concrete and then fix the GH to the battens.

That's exactly what I used to fix my timbers to my concrete block base
wall - of a similar width. Has made a good and secure fixing.
--
Chris French, Leeds

Xref: 127.0.0.1 uk.d-i-y:218547 uk.rec.gardening:160317

IIRC it is possible to get a polyester based adhesive for fitting studs into
concrete.
Take a look at http://www.screwfix.com/app/sfd/cat/...28120&id=16180

Keith

"Grunff" wrote in message
...
Paul D.Smith wrote:
Both yourself and The French's suggested anchor bolts.

Correct me if I'm wrong, but I thought these were like metal rawlplugs
in
that they expand in the holes. At only 4inches wide, I would not expect
the
concrete to have enough torsional strength to hold them in place. In
short,
I would expect to tighten the bolts and have the anchor bolts split the
concrete into two chunks.

If anchor bolts are something else, please fill me in on how they work.

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

--
Grunff

On Mon, 28 Oct 2002 16:48:52 +0000, Grunff wrote:

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

So glue it then, rather than Rawlbolts. Screwfix sell resin cartridges
and the insert bolts.

"Paul D.Smith" wrote in message
et...
A word of warning and a question.

I was given a greenhouse this year. I duly laid a rectangle of concrete
(just the outline, not a complete slab) and built the greenhouse on top.
The greenhouse itself has a rolled steel base and the aluminium frame is
clipped to this steel base. Note that the steel based is NOT fixed to the
concrete - it just rests on it.

OK, you've guessed it; the entire greenhouse slipped 6 inches sideways
this
weekend in the gales. Remarkably, no broken glass. That's the warning
for
those planning to build a greenhouse - "bolt" it down.

Now the question - how? My concrete is about 4inches x 4inches on a
hardcore base (sunken into the ground) so won't take rawlbolts. I'm
considering a piece of dexion hammered into the ground in each internal
corner and then bolting this to the steel base. Do the readers think I
need
to concrete the dexion in as well or would 2ft long pieces sunk into the
ground be enough?

The greenhouse is about 8ft x 6ft and presents the 8ft side to the wind.

I used rawlplugs and number 8 screws to fix mine and it's never moved!

Mine is 6 foot by 10 foot and on a single width brick base about 4 inches
wide.

Alan
--
Reply to alan(at)windsor-berks(dot)freeserve(dot)co(dot)uk

All,

Thanks for the suggestions and advice. I'll be busy this weekend!

Paul DS.

"cormaic" wrote in message
...
'Twas Mon, 28 Oct 2002 16:48:52 +0000, when Grunff
enriched all our lives with these worthy thoughts:

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

4" *wide*??? I assumed that was an error and the OP meant 4"
*thick*. At 4" wide, it's doing well holding itself together!

In that case, I'd use frame fixings to fasten a timber batten
to the concrete and then fix the GH to the battens. If the frame
fixings are at, say 500mm centres, that should be adequate to anchor
the battens and the GH.

--
cormaic URG faqs/webring - www.tmac.clara.co.uk/urgring/
Culcheth Garden - www.tmac.clara.co.uk/garden/
Warrington Paving - www.pavingexpert.com/
Peoples' Republic of South Lancashire

cormaic CAN BE FOUND AT borlochshall.co.uk

Probably shouldn't be replying as I don't really know what I'm talking about
but I happened to be flicking through a Screwfix catalogue at the weekend
(don't ask - very bored at someone's house) and they had several varieties
of screw-like fixings where they were promoting the fact that these gave a
sound fix into plaster and concrete *without* expanding - basically it
seemed they had a fine sharp thread that digs into concrete...after drilling
a hole of course.

Please forgive me if I've said something daft. Lunch is over so I will go
back to doing something I know about i.e. managing parks...

Michael S

Andy Dingley wrote:

On Mon, 28 Oct 2002 16:48:52 +0000, Grunff wrote:

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

So glue it then, rather than Rawlbolts. Screwfix sell resin cartridges
and the insert bolts.

When I last had a greenhouse, I mortared the anchors into the
brickwork base, but found that the differential expansion (work
it out and you will find it is several millimetres) was
sufficient to crack the mortar.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.