Isomastic-A Isomat Caulk Review  By Mike Gregory

Isomastic-A Isomat Caulk Review

By Mike Gregory


I am one of those decorators who have had trouble with paint cracking over particularly big beads of caulk. It doesn’t matter how long you leave it for, some caulks are a right pain in the backside to work with. After going on the Decorators Forum and reading about others having the same issue, I decided to go with a lot of the recommendations on there and try Isomat. This is my Isomastic-A Isomat caulk review.


I didn’t have to order this caulk online, I’m lucky enough to have a stockiest close by. After reading all the positive feedback I decided to buy a box. My first impressions where to do with the size of the tubes and the cost of the caulk. I don’t know why, but they only come in the DIY size of tube which is 280ml. Not only are the tubes half the size as they should be, they are twice the price as a normal sized tube in another brand!!! I thought there was a mistake when I opened the box! As much as this was a shock, I didn’t let it put me off. If it’s so expensive then it must be good….. WRONG!


You need to be careful when opening the tube and screwing on the applicator. If you over-tighten it the thread will break, and caulk will come out of the side. That’s ok, I may have wasted one expensive tube, but lesson learned, and I wouldn’t do it again.


The next issue is the consistency, it’s like water!! It is horrible to use!! You can’t apply a generous bead without it going allover the place. Even applying small beads is a pain because you can’t over work it. If you rub your finger down more than once it cures up on you and you get bits.


Conclusion – I’m sorry but it’s crap. The only plus point is your emulsion will not crack when applied over the top. The caulk itself is expensive, hard to use and very messy.


If you have read this review and you still want to buy it, Isomastic caulk is available off the shelf in some places. The cheapest place I have found online is Paintshack using discount code DF8 at the the checkout. There are better products out there though.

Stay safe – by Pete Wilkinson

Decorator Pete Wilkinson talks about the uncertain times around the Coronavirus, including how it has affected himself and those around him. Stay safe!

Dealing with the Customer from Hell!!

Professional decorator Darren Webb is dealing with the customer from hell. He’s seriously considering telling the silly cow to do one!!

How to Reassure Your Customers During Coronavirus

Professional tradesman Les Bamber talks about how to reassure your customers during the coronavirus outbreak in a bid to protect your business.

Disgraceful Standard of Plastering

Professional decorator Steve Cutbill went to price a small job and found an absolutely disgraceful standard of plastering. Not good

We love picky clients, but Why?

Do you avoid picky clients, or do you love them as much as we do? As long as you have an understanding of a client’s expectations, you’ll be fine.

Another Dreamer – Decorating quote

Professional decorator John Regan talks about the hell he went through when he delivered a quote to another dreamer – 2 hours of his life gone –

Zinsser Gardz before hanging wallpaper

Professional decorator Mike Cupit explains when you should use Zinsser Gardz before applying wallpaper to a room. Is it worth it?

A Fistfight with a Customer from Hell

Professional decorator Alan Saddler agrees mate’s rates and almost ends up having a fistfight with a customer. Horrible situation to be in!

Don’t Waste Time on Paperwork!

Professional decorator Andy Scott has a very valuable bit of advice for anyone in business. don’t waste time on paperwork!

Slow Things Down Get More Done

Professional decorator Andy Scott comes up with a peach of an idea! Slow things down get more done. That can’t be right can it?

Isomastic-A Isomat Caulk Review