This guide outlines the importance of radon-resistant construction techniques to enhance indoor air quality and reduce health risks for homeowners. It details the installation of passive sub slab depressurization systems and vapor barriers, as well as the need for professional installation to ensure effectiveness. Additionally, the document addresses common misconceptions about radon mitigation and emphasizes the necessity of testing after construction is complete.

1. A Guide to Radon Resistant New Construction
By Tony McDonald
Building the Framework

2.  YES
 Your customers rely on you to construct a high quality
safe home.
 You can easily make adjustments to how much radon
gets into the homes you build.
 By lowering the health risk for you customers you can
give them peace of mind about their purchase.
 Indoor air quality is only going to become more
important as a new home feature.
Should I be Concerned about
Radon

3.  Gain Marketing Advantage
 Good Investment for your buyers
 Its relatively simple to install
 Activating is easy
Advantages to Builders for Building
Radon Resistant

4.  Full Basement
 Slab on Grade
 Crawlspaces
 Manufactured Home
 High Levels of radon
can be found in any
of these foundation
types
Foundation Types and Radon

5. Install passive Sub Slab Depressurization System
 What is a passive SSD System?
 system of specialized pipes that collect radon from under the
concrete slab and vent out the roof by passing the indoor air
environment.
 Air moves through the system via thermal differentials.
 More effective in the winter when the outdoor air is colder than the
indoor air.
 Passive systems can reduce radon levels by up to 50% when optimal
conditions exist and the system was installed properly.
 Install an air tight lid on the sump crock to maintain the seal
created by the vapor barrier and increase the pressure within the
SSD system.
Reducing Radon in New
Construction

6. Vapor Barriers
 Vapor Barriers typically 6 mil or thicker, are used to
separate the gravel layer from the concrete layer and
contains the soil gas so it can be routed to the SSD
system.
 Must be installed properly.
 Taped seams
 Penetrations through the slab must be properly
connected to the vapor barrier system.
 On their own vapor barriers DO NOT reduce radon
levels.
Reducing Radon in New
Construction

7. Seal Concrete Control Joints and Floor /Wall Joints
 Helps to reduce radon from entering on ground level
and also helps reduce stack effect on upper levels.
 Final step helps to maximize the efficiency of the
passive system.
Seal Duct Work
 Seal the return air system in a crawl space to reduce
the amount of negative pressure the furnace produces
in the basement.
Reducing Radon and New
Construction

9. System Installed During
Construction

10. Improper Installations

11.  Passive systems are less expensive to install than retro
fit systems.
 If not installed properly will save your homeowner
more money down the road.
 Can be sold as an “up sell” feature in the home.
 It is always advisable to contract a licensed Radon
contractor for this purpose.
Reasons to Install a Passive Radon
System

12.  If radon levels are not controlled by a passive system
alone, it will be necessary to activate the system.
 Activation requires installing an in line fan in the attic.
 Modern fans are available with energy star rating and
consume as little as 12watts.
 Once the house is at final walk through stage is when
it should be tested to see if the passive system is doing
enough to reduce radon levels or is activation is
needed.
Activating a Passive SSD System

13.  Is there a way to test a lot before building?- The
amount of radon that will enter the home cannot be
measured until a structure is built.
 Would I Incur liability by installing radon
resistant features?-You have more liability by stating
there is no need to test because you installed a passive
SSD system without using a licensed radon contractor.
 Are there other ways to tell if the home will have a
radon problem? – NO the only way to know is to test
under “closed house” conditions.
Builder Questions

14.  If I seal all the Cracks won’t that get rid of the
radon problem?- NO Concrete is a porous material
and radon can enter through it. The only way to
reduce levels is with a radon mitigation system.
 Can I spray a sealer on the basement floor and
walls to get rid of radon? – NO Sealers are not a fix.
Radon has been proven to penetrate them.
 If I have my plumber install a passive radon
system it will fix the radon problem?- NO In fact
you are taking on unnecessary liability by not handing
it off to a licensed radon contractor.
More Builder Questions

15. New Construction Lawsuits by
Google

16. www.AZRADON.com

17.  www.epa.gov/radon
 www.radonaway.com
 www.greenbuildingadvisor.com
 www.aarst.org
Other Links for Information

18. Thank you for your participation!!
If you or your customers have further
questions please call our office at (330)
877 5515
Or visit our web page at:
WWW.AZRADON.COM

19. Radon Cloud Chamber