New windows installation with or without brick mould, before stucco ?

Question Icon
Posted by: from Etobicoke
7/24/2012 at 12:48:22 AM

I am planning to replace the wood windows to my 1950 brick bungalow, with new PVC windows, and add stucco with polystyrene for increased heart insulation.

Some window manufacturers recommend not installing brick mould and using just an aluminum capping that will be removed during stucco job (saving also some cost). Others recommend going with the brick mould, so the future stucco job finish would look more professional, and the windows larger.

As I never did any similar jobs before, the un-bias opinion of a professional working with stucco would be appreciated.

Also what would be the recommended thickness of the polystyrene sheet (2" ?, 3" ?, 4"?), and what is typically the price difference (material + labor) between same job done with different polystyrene sheet thickness?

Thanks in advance for advice.


User Icon
Date/Time7/24/2012 at 7:32:28 AM


A window with a brick mold always looks better on a window, more so if your building out the wall with styrofoam.

Cost diffrance on the styrofoam. Depending on the type of styrofoam and the stucco system you are planing on using will determine the price.

On an eifs acrylic stucco system an eps styrofoam is used, and the thicker the better. Cost is not much more per sheet or installation could be around 2 dallors per sheet. However with using a very thick styrofoam with this system, more attation should go into sealing the building envalope. Using a back stop coating would keep any moisture from entering the home. But would have to be applied into the rough opening of the window, before windows are installed.

In a case of not using a back stop coating, and just a house wrap A three inch brick mold, and a two inch eps would work best. One inch thicker then the wall will function much better against the elements.

Conventional stucco. This type of stucco is the oldest and strongest. The problem with using styrofoam with this system Is that by using a styrofoam over 2 inches starts to become problematic because stucco wire is used to attach the stucco to the wall. Using 2 inch styrofoam will be fine, but anything greater will have a good chance to peal away from the wall. The fasteners used for attaching the stucco wire to the walls are roofing nails, The longest roofing nail I have ever found are 3 1/2.

If you are trying to get the best r value for your home with a standard stucco finish. You could look at using an iko aluminum foam board. At a two inch will give you the best r value at the cheapest cost. Anything greater then that sheathing should be removed.

Spray foam the wall cavity, re-sheat the walls and if your going this far the change the sheathing type from a wood to a fiberglass drywall or a cement board, and apply a eifs stucco at what ever type of thickness you what, and can all be glued to the sheathing, back stop coating would be best applied. The end result would be the best stucco system and best stucco look avalible.

If cost is an issue stick with nothing more then 2 inch styrofoam.

Search the TrustedPros directory and discover the best contractors in your area.

Find your home service pro
Great renovations start with a great contractor.

Since 2004, TrustedPros has been helping homeowners find the right contractor for their home improvements and repairs.

Post Your Project

Within hours you'll be comparing offers from top-rated professionals. It's free to post and you're under no obligation to hire.

Trustedpros Inc. does not warrant the accuracy, completeness, safety, legality or usefulness of any Content, or Whether Content is Current and up-to-date, and TrustedPros Inc. Shall have no liability whatsoever with respect to your use or reliance upon any content or for content being removed or otherwise ceasing to be available. Please refer to the terms and conditions of use of this websites for more details.

Get Free Estimates

Post your project and compare offers from top-rated pros.