Veneer Stone #2 The Technical Stuff

As my previous post eluded to – the concept of proper veneer stone installation seems more difficult in the explanation than application. I wanted to install the veneer the best possible way to ensure a long life. Unfortunately – there are multiple ways to put this stuff on a wall and everyone with experience installing veneer stone did it a different way.

This is a pretty tedious post – but I wanted to do this because I have seen so many veneer stone installations that are going to fail in a short time. This post has all the basics – the next post will show how I used the products to install my veneer stone.

So…after months of research and looking at many stone installations I came to the decision to do it this way.

Rainscreen-DetailsPretty simple, right?  Yeah, sure – if your the Einstein of stone masons. My eyes glazed over when looking through all the stuff on the internet. But it really is pretty simple and makes a lot of sense when you start putting it on the wall.

The above is a typical home construction with wood framing over a concrete foundation.

Let’s break it down from the bare wall sheathing to the final stone – and why they’re (to me) important.

WRB – Or weather resistive barrier – most modern homes are constructed with a layer of ‘House Wrap’ Tyvek – Typar or other materials to protect the raw wood sheathing from the weather.  On older houses they may have used a ‘felt paper’ impregnated with asphalt – or nothing at all. This goes on 1st as the last line of protection from water getting in.

Rainscreen – This is next. A layer of material that allows moisture to drain from the wall. If you have a traditional brick home you have a rainscreen behind the brick – a gap between the wood framed house and brick wall. In a veneer stone application you need to use something that spaces the stone away from the wood. I used MTI Sure Cavity because it has a rigid corrugated channel that installs very flat on the wall. This to me is a very important part – all stone, brick and concrete absorb moisture – no amount of sealing, painting or other mumbo jumbo will keep the water out. And when you do get moisture in the wall – you have to get it out. If not – there will be a problem sooner or later.

Weeps – These are the little devices that channel the water from the rainscreen through the stone to the outside. Repeat after me  “You gotta have weeps”.

Flashing – Get you mind out of the gutter because if you did all of the fancy things above correctly and you mess this up – you just wasted time and money for nothing. Proper flashing of windows, doors, sills and other penetrations are top of the list of must do correctly.

Wire Lath – This is the mechanical fastening part of the veneer installation. When bricks are installed, brick ties are used to keep the bricks attached to the wall. With veneer, it’s wire lath. This is nailed securely to the sheathing and wall studs.

Scratch Coat – The first layer of mortar that is applied over the wire lath. It embeds the lath with mortar. Before the mortar hardens is textured with ridges to help key it in with the final mortar bed. That’s why it’s called a scratch coat.

Mortar Bed & Veneer – The final bed of mortar is just like tile – the stone is buttered and pressed in place. I used the same mortar for ‘grout’ to fill around the individual stone joints.

Grout – Serves the same function as tile grout – filling in the spaces around the veneer stone. You would use this if you wanted a special color for the grout.

Other Stuff – Things like Casing beads – backer rods and other accessories meant to make you more confused than ever. But they all have a purpose.

 

So we have the basics out of the way – next time lots of pictures using the above mentioned elements.

 

 

 

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s