Envirograf Clear Heat-Resistant Silicone Sealant – Up to 1200°C

Great product used to seal around the flue on my stove. I applied above the cement that had started to crack and now have an airtight seal. Can't be used in contact with naked flames but worked fine for the job I required it for. Also, the trader was excellent will do business with them again, thanks.

Does what it says. Good clear coloured product. Seems to be heat resistant.

I bought this product to reattach a blanking plate to a 90 degree bend stove pipe that connects my woodburner to the vertical stove pipe. The metal immediately around the screw holes had rusted so couldn't reattach in the normal way. I applied a thin bead round where the glass gasket was, avoiding the holes as I wanted to avoid, as much as possible, the product coming into direct contact with the hot gases inside the pipe. The plate adhered to the pipe with no problem. I let the sealant dry for a day before applying more to the exterior edge of the plate to create a complete seal. I then let the repair cure for a week before lighting a fire in the stove. I built up the fuel gradually and after a short while the sealant began to emit white noxious smoke, which having read previous reviews, I was prepared for. I opened the windows and the back door (and eventually the front door) to ventilate the house. The smoking reduced to nothing over about 30 mins. The colour of the sealant changed from clear to white and on cooling partially back to clear again. The sealant retained a similar flexible feel after the pipe cooled. Happy with the initial result but only time will tell if it survives the full rigours of winter burning each evening.

I used this to fill a gap around our boiler flue, in the ceiling, where muck was occasionally falling down from above - yuk. Via Amazon questions I checked that this was the correct product to use and the helpful maker confirmed it was. The gap was over 1 cm wide in places, and to be on the safe side I filled the hole in two stages. I am an amateur at DIY, so was really pleased (and surprised, given my record at these things) at how neat the job looked. I did use a silicone finishing tool to apply and to smooth off, and I think this was the secret of a good finish, otherwise I would have been in a sticky mess, which normally happens with these jobs. I saw a tip somewhere that recommended frequently dipping the finishing tool in water, and I believe that helped a lot too.

The clear colour and temperature it withstands

The silicon is great easy to apply and did half the job - unfortunately the front part of the cartridge split and I ended up throwing half the silicon away - I out it down to a one off but I am hoping the next one does not develop the same fault It is a great product but annoying this problem occurred

Perfect for sealing around the flue pipe at external wall.

I just used this to seal the small gap between the flue of my stove and the metal plate through which it leaves the building. The gap is about 5mm in places, so I've used a fair amount of sealant. On the plus side, it's not letting the rain in. On the minus side -- it gives off thick white fumes that smell repulsive and make me feel nauseous. Because I've used a lot of sealant, I left it to cure for what ought to be a long time -- two whole weeks, in fact. I lit the fire and allowed it to warm gradually. It's a small stove, so the temperature of the flue pipe reaches only about 300 degrees -- well within the advertised range of the sealant. Over the two hours or so I burned the stove, the rate of fuming did diminish somewhat, from terrifying to rather concerning. However, there's simply no way I could be in the building while the stove is burning. After two hours I gave up, and let the stove burn out. The sealant carried out fuming right up until it was completely cold. Since I have a steel flue passing through a steel plate, there is absolutely no possibility that the sealant is coming in contact with smoke or flames. Sure, it's hot -- but that the whole point of a high temperature sealant. I shall allow the sealant another week to cure, and then try again. If it still gives off fumes I shall have to pick it off, and try again with a different brand. If I have to do that, I shall be expecting a refund, as I'm certain I've used the product as documented. I note that the sealant that is in contact with the metal of the flue has turned brown, although it's still flexible. [Edited to add: I left the sealant another week, with no improvement. So I decided to run the stove at full output until the sealant either caught fire, or stopped smoking. After two hours, neither had happened -- it still smoked ferociously. I shall be asking for a refund. Ideally the seller ought to compensate me for the time it will take to re-do the entire job, but I doubt that will happen. Just don't buy it -- it's useless.]