[Mudge]

Hello All.

I open my greenhouse door every morning on my way to work and close every evening.
Should I be leaving it closed on the cooler days?
Toms, cucumbers, peppers and chillies are in there at the moment.
Thanks
 

[Yorkie]

Welcome to the site and feel free to pop over to the Welcome Board for a proper welcome 

I'm going to move this over to the Greenhouses board for an answer 

[gremlin]

Ah the old greenhouse door morning lottery !

I try to predict door and window settings (and shading) to give about 20deg C max.  But better too cold than too hot. So if I get back and the max-min thermometer has topped 30 deg C I know I haven't opened the door wide enough !

And on a lot of grey damp days like now, I open the door anyway for ventilation.
Today the door has been shut all day - so tomorrow it will be half-opened come what may.

Toms should be OK with the door open. 10 deg C min as a rule.
But the others need the warmth 18 deg min and a steady temp and no drafts

But don't listen to me, I've fried three lots of seedlings in the greenhouse already this year. And all my cu's have died

[Mudge]

Thanks for that.
Seems sensible advice.

[JayG]

I find my automatic roof vent opener is very useful, especially on the days which don't turn out as forecast so you get the door routine wrong!   

[gremlin]

I have an auto roof vent but as it is only a 8 x 6 greenhouse  there is only one opening window in the roof.  I have found it really needs two openings on a hot day so that the cool air goes in the door and the warm air out the roof vent.  I tend to tweak the auto vent to open earlier, or always remain slightly open, if I think it will be very sunny.

Have occasionally wondered about installing a second roof vent,  but it would be £60 or £70 with another auto-opener and not convinced it would be worth it.  BUT then I wouldn't have to worry about the passing cats strolling in through the open door to take advantage of my  greenhouse borders for a nice warm litter tray.

[JayG]

Yes I'm sure two vents at opposite ends and sides of even an 8X6 (like mine is) would work a lot better, but in my case the second one would face the prevailing winds, and on slightly weird days like today (sunny but very windy) the thought of 70 quids-worth of autovent wide open into the wind is not a comforting one!

Although the door doesn't face the prevailing winds they don't always blow from the same direction - it can be quite a tricky balancing act at times!