I have a 4 week litter of 9 medium sized dogs. They have been happy in their box in the kitchen but now need a little more space (well a lot more space probably!)
We have a big conservatory off our kitchen, where we could have the box and an attached run and toileting area....but it's rather chilly out there at the moment especially at night, even with central heating it's big and single glazed and we're having regular night frosts. They have a heat pad and an infra red lamp which they stay away from in the kitchen (in fact we've turned it off) so could use that....but will it still be too cold for them?
My mentors have had Summer litters and have different house set ups, so any advice welcome.

With mine I have made them a 10 x 6 foot covered run outside, with one of those UPV dog houses to den in.

They go out there at breakfast so I can clean the indoor pen, and then come back in and out in the day, and in the evening back into the kitchen pen.

They seem happy enough to be more confined for the evening/night, after having the opportunity of more space and play through the day.

Here's what I do -
I have a small boxroom/computer space downstairs where I have my pups from around 2 weeks old(before that, whelping box is in my bedroom).  I take the door off and replace it with a babygate so the pups can be shut in but still see/hear everything going on.  This is where the pups sleep at night till around 5 weeks old.
I also have a utility space at my back door which leads onto a large patio area.  This is where the pups spend all day with the door open so they can go in and out as they please.  With winter litters, we wrap up warm all day!!lol.  The utility area is made up as the 'bed' and food area and the paper is place just outside the back door.  I am very proud of the fact that my litters are very clean and easy to housetrain because of this.

Thanks...sounds like two locations are the answer for the next week or so, will make keeping everything clean easier anyway :)

A friend of mine uses a similar system but uses her porch as the pups sheltered area and attaches a puppy run outside it with door open for outdoor safe space.

In my case the puppy pen and hut are outside the back-door, with a step over barrier,a nd once they are about 7 weeks they will usually be over it and running in and out of their own accord utilising the whole dogs area along with the adults.  By then they are pretty much fully weaned so they don't pester grown ups.

Still go in the kitchen pen at night.