Doing my DIY conservatory in Winter! sealants

[bodgeroony]

well hindsight is a great thing, and should have built in the spring in the rain perhaps!
but are low modulus neutral cure sealants ok to use under 5C?
are there serious reasons that many of the products say 5C, what if its 3C in the day and 0 or 1 at night?
I have found a few products with a tolerance to cold, but all of their suppliers are closed this week - doh!

 

[Donkmeister]

I wouldn't risk it... the danger is frost. Expanding ice crystals will knacker any seal. Wait until it's a little warmer if you can.

I wonder if putty would be suitable? Just so long as you can get it warm enough to work with, of course.

It's not mastic, but I made the mistake of using "quick dry" varnish on a front door in cold weather. The can said it took 20 minutes to become touch dry, 5 hours later it was still completely wet and my house was freezing!!! It took a few weeks to become properly hard.