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Builder & Developers FAQs

  • How do you fasten the baseboard in a Nudura house?

    The best way is to rip a plywood strip 2 to 2 1/2" wide and screw it in place to the webs along all the walls. Fasten these strips at every fourth web. Now the drywall contractors can set their drywall on top of it and will cut their top sheets accordingly to suit this height. The result is you have full wood fastening for nails along the complete wall surface and the plywood is guaranteed to be covered by the baseboard.

  • How do you fasten a typical 1104 type box to the walls?

    Our form panel thickness is 2 5/8”. This is deep enough to accommodate almost every standard depth electrical box. Deeper boxes are easily accommodated by simply gluing a square of foam on the inside of the form at the location being planned for the box during the pre-pour phase of the installation process. 

  • How do you attach siding, drywall or other finishes to Nudura ICF?

    The Nudura form unit has a fastening strip located every 8” (200mm) on center. These fastening strips are continuous up the full height of the form unit and have a mechanism that interlocks one fastening strip to the one below it or above it. These fastening strips are indicated on the surface of the form by a diamond pattern. They are 1 ½” wide and have a higher pullout strength than a dimensional stud. Different types of cladding will have different installation procedures.

  • What type of screws do I use to fasten vinyl siding?

    A standard #6 x 1 ½”  to 1 ¾” coarse thread “bugle” style or “flute” head (1/4” dia. head) zinc-coated or otherwise non-corrosive screw will do nicely (NOTE: as inexpensive as they are - drywall screws with the black sulphur coating will eventually corrode).  

    Equally as useful are standard bright (chrome-like) finish #6 or # dia. x 1 12” pan head coarse thread self-tapping screws. These have the added bonus of being able to be used for a multitude of anchorage purposes besides siding fastening and do not corrode as easily as drywall screws.

  • Where should I make my cuts in a form unit to achieve the desired length of wall?

    To achieve your desired length of the wall, you will have to use standard form units, corner form units, and then remove certain lengths off each of these to get the desired length of the wall. The form is designed to make measuring as easy as possible for the installer. Each interlock along the top and bottom of the form is 1”, and the scoreline on the outside of the form panel denote 2”. By knowing that the webs are 8” apart, you can use these three units on the form to find where you need to make your cut. 

  • Are there any VOC’s or gaseous emissions from the foam block?

    In our Nudura Insulated Concrete Forms, the webs are composed of high-density polypropylene, made from 100% post-consumer recycled plastic. This plastic is totally inert and emits nothing. Copies of the MSDS sheets for the virgin version of this material are available from either Nudura’s Technical Service Department or your local Distributor.

  • Can concrete be poured into Nudura Insulated Concrete Forms in cold weather?

    If the average temperature in a three day period is below 40̊ F or 4.5̊ C then this would be considered to be a cold weather pour. Concrete can be heated and the mixture can be altered as well for this scenario.  Provisions can be made so that the full compressive strength of the concrete can be achieved in these lower temperatures.  If you have further questions please contact your local distributor.

  • How do you remove snow from the bottom of the form?

    The solution to this problem is to cut a hole in the bottom of the wall the diameter of your forced air tube. By connecting a piece of duct to this hole, you can force warm air through the cavity and cause the ice to melt. To achieve this as quickly as possible, it is best to cover the top of the wall with an air barrier to hold in the heat.

  • What are the best increments to use for stepped footings?

    When using the Nudura ICF for a foundation wall, and you have stepped footing, the best possible increment to use is 18” (450mm). As the height of the form unit is 18”, you can rip a standard form unit in half for a 9” (225mm) increment. This is also a favorable increment to step footings.

  • What is a lift height?

    Lift height is how high you pour your concrete in one pass around the perimeter of your wall. By ACI 318 standard practice, your lift heights should be 4’ (1200mm) per hour.

  • What is the total height of a pour?

    Concrete is typically poured in 10-12’ (3050-3658mm) levels. Therefore according to the last question and answer, a typical pour consists of 2-3 lifts.

  • How is concrete properly consolidated?

    When consolidating concrete after it has been poured, one must do it in a consistent manner, dipping the ‘stinger’ the total height of the ‘lift’.  This type of vibrator should be dipped into the concrete every second web.

  • Will I have to worry about mold growth with Nudura ICF's?

    The EPS foam is an inert material, meaning it is very slow in any reaction, and there are no active properties to it. This does not mean however that mold will never propagate on an ICF wall just because it uses EPS as insulation. The truth is, if you do not have sufficient airflow, you can accumulate an excess of moisture through condensation at your openings. This build-up of water, if not evaporated, will eventually cause mold to grow on the paper of the drywall. This is why, when dealing with your HVAC system, you must adjust it accordingly for a tighter building envelope, therefore requiring more air exchanges

  • How high can I build with Nudura?

    Typically in the past people have thought that ICF is only good for foundations, however, this is a myth. The truth is if the structure is engineered, you can use Nudura to build up as high as you please. Of course, as the building gets taller, the thickness of the wall will increase. The reinforcing steel within the wall may get thicker or spaced closer, or you may simply have to use Nudura as an infill or curtain wall with a post and beam structure. Our prescriptive data will take a residential project up 2 storeys before requiring engineering, but there are many projects on a commercial level that have gone up multiple storeys using the Nudura ICF to form structural walls.

  • How is Nudura a ‘Green’ building product?

    Nudura is Green in a number of ways. The material of the webs is 100% recycled. The material for the foam is 100% recyclable. The EPS foam emits no CFC or HCFC’s or VOC’s. Using Nudura as opposed to traditional building methods cuts down the amount of wood used, which has become a precious commodity. By minimizing mold growth and giving a more sound proof home, your indoor comfort is increased dramatically. By reducing waste and shipping space required, Nudura also impacts the environment in a very positive manner. These are just a few of the reasons why Nudura ICF is an environmentally innovative material to use in your buildings.

    For more information on Nudura Concrete Forms green attributes visit our building green section for more information.

  • How thick can I make my Nudura walls?

    Nudura Insulated Concrete Forms come in 5 different core sizes. Standard thickness are 4” (100mm), 6” (150mm), 8” (200mm), 10” (250mm) and 12” (300mm). Nudura also sells the form units in unassembled forms as well for flexibility. With the new 4 Way Web Connector, you can now take any of the thicknesses mentioned above and combine them for different combinations of larger sizes. Ask your local distributor about the 4 Way Web Connector and what you can do with it.

  • Do my designs and plans have to be done specifically to Nudura’s ideal dimensions?

    Your plans do not HAVE to be designed to Nudura ideal dimensions, though it would help the construction process go faster if the modular dimensions of the form unit are considered, however, Nudura’s forms are flexible in that you can adapt it to an existing ICF design. Should you want to design using Nudura’s most optimal dimensions, ask your local distributor for the Dimension Layout Guidelines.

  • Where is waterproofing necessary?

    Although the joints between the Nudura form units are tight, below-grade waterproofing is still necessary. Nudura sells a peel and stick waterproofing, that is easy to apply and carries a warranty of two years. This membrane must cover the foundation walls. In situations where you have an attached garage, the below-grade wall shared with the basement must be covered, and a 4’ (1200mm) overlap to the adjacent walls.

  • Do I still require a vapour barrier with Nudura?

    According to the standard ASTM E 96, to qualify as a vapor barrier, a material must not exceed 45 ng/Paּsּm². This unit denotes the ‘permeance’ of the material, meaning how much moisture per force applied (air pressure), in a second over a square area. Our EPS foam has a permeance value of 36 ng/Paּsּm², therefore the Nudura Type II EPS qualifies as a vapor barrier. 

Nudura Training Academy

Learn from our experience. If you are thinking of building with Nudura Insulated Concrete Forms, we encourage you to take one of our One Day ICF Training Courses. The One-day training seminars provide the basic Nudura ICF installation skills

Project Applications

Nudura is proud to be the insulated concrete form (ICF) of choice for hundreds of project across North America in both residential and commercial settings.


We’re committed to supporting homeowners and design professionals who are interested in or use our products. We’re always happy to help and provide more information.