# Forum Home Renovation Painting  exterior paint for use in interior?

## montiee

I was wondering if there were any disadvantages to using exterior paint inside the house? Is it more toxic, poorer finish etc? 
Specifically rather than waste half a can of paint as usually happens etc I'd rather buy exterior white semigloss acrylic and be able to use it both inside and out as I'm doing the entire house. 
Also while I everyone's attention semi-gloss is typical for doors and trim right?. Acrylic won't yellow either right? 
Finally is Nippon paint any good? 
Cheers
M

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## Axel

There are several disadvantages to using exterior paint inside: 
- Exterior paints generally stay softer than interior paints, expecially in hot weather.
- They normally need exposure to UV light to cure (cross link) properly.
- They have less stain resistance than interior paint and are harder to clean.
- They have more/stronger anti mould chemicals in them which will continue to affect your interior air long after the paint cures.
- The sheen levels are often higher than interior paints and they may look and feel different. 
It might not be a disaster and i'm sure a lot of people do it. I wouldn't.  
I have used a bit of Nippon interior paint and have found it to be excellent. Great application, coverage and finish, it covered hairline cracks that other paint wouldn't have and had a very low odour. Of course wattyl, haymes, dulux also make good paint in Australia...

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## montiee

Thanks. Surprised about the harder to clean exterior pain comment though. Houses get way dirty outside than in with all the dust and crap from mowing..  
hmm decisions...Bunnings guy said no different except exterior paint has uv stabilisers in it (makes sense) but then it is a bunnings guy.. 
Any pro painters care to comment?

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## Axel

Bunnings guy is wrong. Look it may seem counter intuitive that interior paint is easier to clean than exterior paint but you have to think about it in context. 
Exterior paint needs to withstand heavy rain, lots of dirt, mould, temperature changes, movement in the substrate etc. As a result exterior paint is flexible (softer), has more chemiclas (VOCs), and the way it resists heavy dirt and pollution is not by being easy to wash/scrub but by shedding or chalking very small amounts of its surface. 
Interior doors and trim requires paint formulated to be pretty much opposite to what exterior wall paint is.

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## Lumnock

I also am a Bunnings guy, and Axel is spot on the money.  Don't use them inside for the reasons he mentions in his first post.

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## montiee

Bought some dulux acquaenamel. According to duluxes site it's ideal for trim. Can says exterior and interior use  :Shrug: ..Works for me  :Smilie: . I guess solely exterior paints might pose a problem.

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## Axel

Ok mate that's a bit different! Trim paint is often fine for exterior or interior use. When you say exterior paint most people (well me) would think exterior acrylic wall paint - eg solagard, weathershield etc.

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## montiee

> Ok mate that's a bit different! Trim paint is often fine for exterior or interior use. When you say exterior paint most people (well me) would think exterior acrylic wall paint - eg solagard, weathershield etc.

  Yeh weathershield etc was what I initially meant. In the end I went with what the dulux website recommended for trim and coincidently was rated for both.. At that point I had resigned myself to buy an interior specific paint.

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## montiee

Thanks everyone for the replies and help.

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