Our Insulation thoughts; what is the best financial investment to achieve the end goal of good insulation, good indoor air quality and sound control?

 After you’ve completed sealing the thermal envelope, what goes behind the drywall is a big decision. Let’s start with basics.

 INSULATION / R-VALUE

R-Value is a measurement of thermal efficiency or measurement to the resistance to heat flow. The higher the R-Value numbers the greater resistance the insulation has to the movement of heat.

A large percentage of heat escapes through the attic and walls of a home. In order to build a better thermal envelope, we accept that heat flows in one direction, from warm space to cold. Example, warm inside air will flow to the outside during winter months. The most common insulation method is fiberglass insulation batts, which are placed between the studs and stapled into place. The drywall is then nailed over, creating a wall. Although this is an acceptable method, it can be done better. The fundamental problem with the batt is you need to ensure there aren’t any gaps and you can’t because those insulating products are manufactured true and square. In a real-world environment, cavities between the studs are irregular and additional trades cause other obstructions like plumbing stacks or HVAC trunk lines.  You also have to work around supplementary roof and wall penetrations associated with utility and/or local communication companies that create hard-to-reach places creating pathways for conditioned air to leak in or out, sacrificing comfort.

Why Spray?

Because this delivers a continuous thermal and air barrier that seals around plumbing, vents and electrical openings as well as other cracks and voids that allow unwanted air leakage. Leaving no gaps or seams, it minimizes airborne irritants such as allergens, drafts, or humidity.

The following are spray-in custom insulation materials that provide superior performance in relationship to the above acceptable building method.  

Icynene insulation delivers advanced moisture management by forming an air seal to minimize air movement. By minimizing air transported moisture through the building envelope, Icynene helps to prevent condensation and reduces the potential for mold growth within walls and ceilings. Icynene products feature 100% water-blown technology. Using Icynene insulation in place of an air-permeable option can dramatically reduce a building’s carbon footprint by as much as 50% since less energy is required to heat and cool the building.

http://www.icynene.com/

Johns Manville Spider® custom fiber glass insulation is available in variable thickness levels. It  can fill 2x4 cavities up to an R-15 thermal rating, 2x6 cavities up to R-23, JM Spider® insulation also reduces sound transmission, achieving a Sound Transmission Class of 43 in a standard 2x4 wood-framed wall. JM Spider® insulation resists mold because it sprays in almost dry (less moisture content than wood framing), and is treated with a U.S. EPA-registered mold inhibitor to protect the insulation against mold. JM Spider® insulation can be used for both wall and ceiling applications. In addition, only fiber glass insulation made without formaldehyde—such as JM Spider® Custom Insulation—can pass Environmental Specification 1350, the toughest indoor air quality test in North America, with a non-detect for formaldehyde.

http://www.specjm.com/products/sprayin2/spider.asp

If you have additional questions on insulation, please contact us  @ info(at)cdbmd.com 

Cheers!!

We are currently preparing for close-in on one of our more unique and challenging custom homes. What makes it challenging? Two factors; it’s a significant renovation; which meant keeping the original foundation built in 1960 and then constructing a magnificent modern designed structure.

Our client is extremely concerned with energy consumption. To this end, we thought we would blog about “common household air leaks” and what to do. The main areas to address are:

• Behind Kneewalls
• Attic Hatch
• Wiring Holes
• Plumbing Vent
• Open Soffit (the box that hides the recessed lights)
• Recessed Light
• Furnace Flue or Duct Chaseway (the hollow box or wall feature that hides ducts)
• Basement Rim Joists (where the foundation meets the wood framing)
• Windows and Doors

At Congressional Design Build, we subscribe to the theory that if you insulate properly, you can heat and cool your house with a match … we’ll almost. Start by sealing the thermal envelope. This is part of the house which separates the indoors from the outdoors, and consists of the floor on the bottom level, the ceiling on the top level, the exterior walls, the exterior floor bands, and of course the doors and windows.

How?

• During the framing process make sure you seal under the exterior walls; we use a special wall gasket
• Use housewrap (tyveck or equivalent) on the exterior framing at the floor band just below the walls, and to the very top outside of the exterior walls. Follow installation instructions
• Caulk under exterior doors before installation
• Seal around windows and exterior doors using caulk or poly foam sealer (great stuff) that is specified for doors and windows. Don’t use the regular expanding foam sealant …just don’t!
• If your attic will have blown insulation, ask to build a box around the access hole so the insulation can come all the way to the access hole without spilling into the house.
• After wiring, plumbing and HVAC have been roughed in and before installation of insulation, use foam sealant in all of the holes that have been drilled through the top or bottom plates of all walls; not only the exterior walls. The interior walls are important too; air will exchange from the interior to the crawl space and the attic through interior walls.

We would recommend hiring an insulating company to perform the above and make it part of their Turn-Key solution. In the Washington Metropolitan Area they call it “Air Control and Draft Stop.” They typically use a foam sealant and a high grade non-sag caulk for air control and we would recommend an STI Fire Stop product.

Next we use spray-in custom insulation materials that provide superior performance, we’ll tell you who they are and why it’s superior on our next blog entry. 

Cheers, Team CDB

Glass Treads Anyone?

We received a phone call from a prospective client asking if we have built a custom staircase with glass treads?  The answer, no; however, we have built several custom homes with glass rails and have worked thru the idea of incorporating the tread with several local metal fabricators, but the final cost has always been the contributing factor to not moving forward.  To this end, if anyone is looking to build a custom home with an entire glass stair and rail, we would love to assist in making it a reality.

For those of you outside the Washington Metropolitan Area, but require additional information on whom and how, email us or our local rep Ann Kerstetter at amkincmd@verizon.net  or click www.amkinc.com. She represents Joel Berman Glass Studios located in Canada. The studio creates and manufactures a wide array of textured cast glass, tempered and annealed of varying thickness.  It can be transparent, translucent, sfumato and opaque and in almost any color.

Bar Trivia

What is sfumato? It’s a glass-blowing technique, creating faint gradation of color from transparent to opaque. As light spills through tiny air bubbles in the glass, sparkling, textured patterns are cast on adjacent surfaces.

Win a drink on us.

Cheers, Team CDB

We received an e-mail asking for any ideas for a light transmitting counter-top for a basement bar?

While several come to mind, there is one we are currently using we think is cutting edge cool. Not to mention, their local rep has wowed us with their customer service, which is extremely helpful when it comes to working through a complicated custom “S” curved counter-top that glows. As they say, “The Devil is in the details” and their shop hasn’t missed a beat.

Oh, did we mention it was COOL? If you scratch it, simply take a Scotchbright pad and buff it out! The surface can handle commercial paint remover and harsh chemical cleaners, so bring on the kids. And on a side note, they can even make it bullet resistant. Yes, we have received this request before, but for an office window, not counter-top; however, this product has unlimited potential.

Click on www.lightblocks.com; they will fabricate to your specifications in any thickness, color, opacity, size and resin. Their process uses no solvents; no VOC's are created, and from what we understand, all of their scrap is recycled.  They have an average of 98% utilization of raw materials and the product qualifies for LEED points.  

So, if you’re in the market for something out of the norm, send Jacqueline Downie an e-mail at (jacqueline@lightblocks.com) for additional information.

We are also interested in hearing about new and unique building materials, feel free to e-mail us at info@cdbmd.com with such information.

Best, Team CDB

Today my neighbor asked me...

Today my neighbor asked me over to look at his concrete stoop. As I got closer to the steps, I noticed that the concrete surface was scaling.  Thinking it was builder error, I asked him if he had been using rock salt as his ice melt?  He said yes! Well, that’s the culprit and here’s why:

While concrete can be one of the longest lasting surfaces you can use, its useful life will be reduced if its weaknesses are exposed. When subjected to tension, concrete is at its most vulnerable. In colder climates, freezing causes the water in the capillaries of the concrete to expand, creating pressure. Yes, while concrete appears very dense, it acts like a dry sponge; it loves to absorb water. The use of rock salt accelerates the melting process. The water enters the concrete and begins to freeze; growing ice crystals create pressure and BAM! Break away the top surface, leaving pit marks exposing the coarse aggregate. We call it scaling or spalling. Also be aware that this can happen on concrete drives as well. Salt and deicing chemicals are picked up from the road and dripped onto the surface.

What can you do to prevent this? Use deicing products that don’t have rock salt or sand.  You can also treat your concrete with a clear coat, but be careful to avoid products that use silicone. It creates a seal trapping water, preventing it to evaporate. Yep, you guessed it, the top surface will scale. So, always contact a reliable contractor to assure the job is done right.

Cheers, Team CDB

Today I received a call asking our standard vanity height? 

Since everything is normally custom, it’s driven by our client’s personal program, but I would have to say it’s usually 29” to 31” high.  There was an occasion we built to 40”, but he was 6’5” and I built my personal ones to 36" high.  Remember to take the following into consideration:

Most vanity tops are ¾” or 3cm thick

In secondary bathrooms, I would set them lower because the area is shared with children and should wash their hands, too.

Another factor will be the type of sink you select, the ones that are installed on top of the counter-top, you should use a lower height vanity or you’ll wind up with the top of the bowl about 40" to 42" if used with a 36" high vanity.

Now, notes on building 36” high, if this is what you select, make sure to take into account the location of your bathroom door and swing. Most door knobs are set at 36” which makes for an interesting situation when you want to open a drawer. I know, because I thought I would build my own to the same height as our kitchen cabinets, which are 36” and well, we have a cased opening into our bathroom. 

"Good judgment comes from experience.  Experience comes from bad judgment." -Bob Packwood

Cheers!