Do EIFS require Expansion Joints?

Expansion joints in EIFS are required at the following locations:

• Where they exist in the substrate or supporting construction.
• Where the EIFS adjoins dissimilar construction or materials.
• At changes in building height or other areas of anticipated building movement.
• At floor lines in multi-level wood frame construction.
• Where prefabricated panels abut one another.
• Where the substrate changes.

2.

How wide should expansion joints be when installed with the EIFS?

This issue is the responsibility of the design professional.

3.

Can a "V" groove reveal be considered a Control Joint?

A "V" groove reveal are aesthetic and cannot be considered a control joint since a true joint is a "built-in" break in the system where cracking is anticipated. Reveals in EIFS are strictly aesthetic joints and are used to provide convenient stopping points for finish application in large wall areas. If movement relief is necessary, a full expansion joint with sealant is necessary.

4.

Is it necessary to install sealants?

Yes. Sealants are always required around windows, doors, all wall penetrations, and at the juncture of dissimilar materials. This is true for every type of wall cladding. Sealants are not a part of an EIFS; however, their use in conjunction with the system is a necessity. Moisture damage caused by failure to properly apply sealants at those points just named is not covered by manufacturers' warranties.

5.

Are there alternatives to sealant joints around my window?

No. The sealant joints around the perimeter of your windows, and the sealant around doors, dryer vents, hose bibs, and every other penetration serve a critical function; they help keep your home tight and help in keeping water out of your walls. If the sealant is properly installed as specified by the sealant manufacturer, these can give you many years of protection.

6.

What types of sealants are recommended for use with EIFS?

In general, low modulus sealants that maintain their properties with exposure to ultra-violet (UV) light are recommended. In addition, the sealant should comply with ASTM Test Method C1382-97. Of course, in the selection of any sealant, other functional factors must be considered such as anticipated joint movement, substrates to which the sealant will be bonded, exposure to cyclical movement, and exposure to temperature extremes. Always consult with the sealant manufacturer for guidance on suitability, design, and proper use and handling of their product.

7.

Why must a closed cell backer rod be used with EIFS?

The use of closed cell backer rod (instead of open cell) behind sealants is recommended to prevent premature failure of the sealant joint. Open cell backer rod will absorb and hold water that could affect the sealant/EIFS bond line.