Zinsser Gardz Review – the Full Truth

As a Professional Decorator, I’ve been using Zinsser Gardz for around 9 years. It was available before then, but Decorators hadn’t really heard of it. I can remember walking into Dulux Decorator Centre asking about it, and them just looking at me with a confused look on their faces. Now, most Decorators use it and love it, so I thought it was about time I chipped in with an honest Zinsser Gardz review.

What is Zinsser Gardz?

Zinsser Gardz is a water-based stabilising solution for interior use. It’s clear, thin, and goes for miles. You can apply it with a brush, roller, or airless sprayer. You might use it to stabilise walls, neutralise wallpaper paste, seal plasterboard, prime filler, even tackle flaky paint on a bathroom ceiling.

Zinsser Gardz is touch dry after around 30 minutes, but you should wait 3 hours before applying other materials over the top. 1 coat of Zinsser Gardz is generally all you need. It binds loose material and creates a moisture-proof film that can act as a barrier coat between a problem substrate and new decorating materials. This is slightly different to Zinsser Peel Stop, which also acts as a stabiliser, but remains breathable and flexible.

I think what I’ll do is work my way through the different jobs I use Zisser Gardz for and explain what I like / don’t like about the product.

Zinsser Gardz to Prime a Wall Before Wallpapering

I wrote a full blog on using Zinsser Gardz before applying wallpaper, which you can view here, but I’ll touch on it in this review too.

Ideally, you’d size walls before wallpapering, or use a primer like Beeline, but if the walls are in particularly bad nick, then Gardz is brilliant. You just use it like any other primer, but it really bonds an unstable surface. Then any little grains of plaster that get caught in the film can be sanded smooth. This is where Gardz differs from other products. It’s much easier to achieve a very smooth surface with it.

You might strip the old wallpaper, sand down, fill, sand again, then apply Gardz. This gives you a very stable base. You can carry out any spots of filling you missed on the first round, sand the whole wall again, then apply the wallpaper.

Wallpapering is also easier if you’ve used Zinsser Gardz to prime the walls. You get a certain amount of slip between paper and wall, which means you need to apply less pressure to get the paper in place and smooth bubbles out.

Ready-mixed paste is advised if you’re papering onto a wall primed with Gardz. Flake isn’t strong enough to adhere to a non-porous surface.

Zinsser Gardz to Neutralise Wallpaper Paste

Say you have stripped wallpaper from a wall that you intend to paint. No matter how much you clean the wall, you won’t get rid of all the paste residue, which might react with your emulsion.

Zinsser Gardz is the perfect solution. You don’t need to clean the walls to the same level as you would if you weren’t using Gardz. Apply a quick coat, wait 3 hours for it to cure (don’t rush this or you’ll experience crazing), fill, sand, then paint.

Not only does Zinsser Gardz stabilise the wall, but it also blocks in any nasties like wallpaper paste. It’s a safer, better way to go about prepping a wall that has been stripped.

Zinsser Gardz to Seal Excess Filler

I had a job recently where I stripped wallpaper on one wall, surface filled 2 other walls with Toupret, and then sanded everything ready to paint. Filler once sanded becomes very chalky. I was in two minds whether to prime with Zinsser Gardz or use a mist coat.

I had to get the Gardz out anyway, and it’s a product that is very quick and easy to apply, so I coated all of it. But before I did, I put a little video explaining my dilemma on social media (the video is below).

A lot of the Professional Decorators who answered (not all of them) said they’d coat everything with Zinsser Gardz.

This made sense to me. Gardz is one of those products that you ‘might be able to get away with not using’, but you can always rely on it. You know if you use it, you’ve done your job properly. Zinsser Gardz will never let you down, so you’ll never have a problem further down the line.

Zinsser Gardz to Prime Plasterboard

Tape & joint (drywall) is an alternative to plaster. It’s cheaper, so builders opt for it on occasion, and then it’s hidden by paint anyway. It can cause problems when sanding further down the line, or if the wall is ever wallpapered.

Plasterboard is way too porous, and it’ll disintegrate if you ever need to do any serious work on it. A quick coat of Zinsser Gardz solves the issue. Not just for now, but for as long as that wall is part of the house.

FAQs

Can I paint directly over Gardz?

You can paint over Zinsser Gardz with almost any paint. You must wait 3 hours after applying the Gardz, otherwise you may encounter crazing. I’d also avoid using cheap contract matt on Gardz.

Can Zinsser Gardz be used on wood?

You can use Zinsser Gardz on wood, but I don’t see why you’d want to. If you need a clear stabiliser/primer for wood, then Zinsser Peel Stop is far better suited.

How many coats of Zinsser Gardz?

You only ever need 1 coat of Zinsser Gardz. It’ll do everything it needs to do, and you’ll be left with the perfect base on which to work.

What roller is best for Gardz?

A fluffy long-pile roller like the Purdy Colossus is best for applying Zinsser Gardz. Remember it’s a very thin material, and you’re often applying it to a porous surface. Also, roll from the bottom to the top of the wall and move very slowly. This will help reduce spatter.

Is Zinsser Gardz breathable?

Zinsser Gardz isn’t breathable like Peel Stop is. It creates a moisture resistant barrier.

Can I use Gardz over wallpaper?

No. Contrary to the advice I’ve just read on a different blog, Zinsser Gardz is used as a stabiliser on porous surfaces. You wouldn’t use it on a non-porous wallpaper. I don’t see what benefit it would offer, even if you could.

Can you fill over Gardz?

You certainly can, and I often do. Allow the Gardz it’s proper cure time, then fill or skim over it as you need to.

Summary

Final Thoughts

You now have my honest Zinsser Gardz review. It’s a hard-working, problem-solving product that still doesn’t get the praise it’s owed. I think it’s brilliant, and it’s one of those materials I wonder how I ever coped without.