Will slabs make my gh too hot?

[mikon_warrior]

hello again, Someone on the allotment told me to take out the slabs from gh as it will act as a storage heater and will get too hot so nothing will survive, i can see her point as it got to 42 degrees in there the other day and it was only 20 outside. What is the ideal tempreture???

Would you agree???

ta

sarah

[Snadger]

A lot of people use paving slabs as a base for their greenhouse without any problems! In summer you shouldn't be able to see the flags apart from where you are walking as the foliage will be covering them. If they do act as a night storage heater, so what, it will help to even the temp on cold summer nights! It could make the difference between it being frost proof and not in winter.

[Finedon.Dandy]

Here Here!!!

[crichmond]

No problem with slabs here, just make sure you have ventilation if you are worried, I have autovents that open at around 20 degrees so the greenhouse stays around 36 degrees.

[j r hilton]

I have had slabs in my g/house for years with no problem. I have an automatic vent in the roof and if need be open the door for more ventilation. Ventilation is the most important requirement.

[workhorse]

You should also consider damping down the slabs with water. This will help cool things down, and add humidity as well.

[Cutecumber]

I guess the problem is that the greenhouse is on your allotment so you can't get there to open and close all the time. Is it a fully slabbed floor or is there just a path? Keeping slabs to a minimum, i.e. a central path is quite common.

Autovents are essential if you can't get to the greenhouse regularly, but it will still get mighty hot - a paint-on shade can help a bit.

Fully open, our greenhouse hits 38 degrees regularly through the summer despite damping down as much as possible. I throw a green netting shade over the glass in exceptionally hot weather to stop it creeping into the 40's but this is not an ideal solution.

Chillis and aubergines do well as long as they are kept moist. Cucumbers cope admirably but would prefer it slightly cooler. I have found tomatoes in pots or growbags hate it once the temps get into the upper 30's - they need planting in the border at least. I only grow them outside at the moment.

[Flummery]

I just have a narrow (1ft wide) flagged path down the centre. It's good for damping down to increase the humidity.

[mikon_warrior]

Hi there, mine is full with slabs and yes i have a problem with getting to the allotment to open the door etc. I will have to look into getting an autovent to see if this helps. I have been up today and have noticed that some of the leaves on the seedlings have gone a little yellow - im assuming they have been scortched??? To be honest im not growing much in it - was just going to use it to get a head start on the veg but it seems to be to much trouble at the moment. It would be ideal if it was at the bottom of the garden. i was going to do chillies and peppers this year for a starter.

I feel very lost and need a crash course in greenhouses!!! oh well. Im sure im worrying over nothing, just dont want all my hard work go to waste when i plant out my little plants.

Surely if im having problems now whats it going to be like in the height of summer???

[Matt.]

As you don't have an autovent I'd consider leaving the window open permanantly. You'll be suprised how warm everything stays. Also it helps recycling the air and avoiding damp based fungus problems. Just be carefull if a really windy day is forecast.

Also check how you are measuring the temperature. Is the thermometer in direct sunlight. That makes a big difference.

[mikon_warrior]

Just to say thanks for all of your advice, I have now got an autovent (homebase 16.99 - bargain) and some shading paint. Guess what i will be doing tomorrow...

[bluemoon]

I've used slabs for years. True they do act a bit like a storage radiator, but that can be an advantage in winter, it also means you can damp down and not turn the greenhouse into a mudbath.

[mikon_warrior]

Yey, Autovent fitted (what a kerfuffle) thin layer of greenhouse paint on the sunny side.... just need to start some more potting and getting some cheap and cheerfull staging - my table fell to bits... oops

Thanks again - lets see how i go now...