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Thinking about insulation? Take a whole house approach to insulation.

A Whole House Approach. When contacting insulation companies for multiple quotes, homeowners often have done some research. If the research is misleading or not applicable to their structure, they can make the mistake of paying for an insulation treatment which yields little to no benefit. Ten things to ask your insulation estimator. 

1. How can you help me identify moisture transfer, and is there a moisture issue creating a food source for mold?  

2. How can you help me identify air transfer which is making the home drafty and making some rooms colder than others in winter and hotter in summer? 

3. What are the existing types of ventilation, and how are they calculated? 

4. What gaps in the pressure barrier ( building envelope) exist at present and what action can be taken to seal them? 

5. Type of existing insulation, please identify the R-Value and Material?  

6. Pros and cons of adding new over existing insulation?  

7. Did you find or attempt to locate any entry points of critters, birds, bugs etc? 

8. Did you identify and provide a solution for multiple air escape paths / routes? 

9. What areas for improvement need to be completed by me the homeowner that your company does not provide paid services for? 

10. Cost comparisons of different insulation materials and breakdown of costs and breakdown of sq ft treatment ? 

These 10 questions are in addition to the obvious top 10 you find on google such as

Make sure to ask for bids to be submitted (in writing) with the following:

  • The coverage area to be insulated
  • The installed R-value (not the thickness but the final R-value when everything is completed)
  • The total cost (is it an hourly rate, fixed price or based on coverage area?)
  • The schedule
  • Expressed warranties for the work
  • Potential issues the contractor might face during the installation process

Ask the insulation contractors things like:

  • How long have you been in business?
  • Do you have a license (if necessary) to operate in the state?
  • Are you a member of the Better Business Bureau?
  • Do you have insurance to cover any accidents while working on the project?
  • How do you handle customer complaints?
  • What types of insulation do you install?
  • Do you have references I can contact?

Baffles In Every Bay Not Just Quot Where Ventilation Is Present Quot

Tackling Air Leakage : Making your home cooler in summer and warmer in winter while lowering gas and electric bills. 

Green Attic Insulation can insulation over the attic floor or between stud cavities of walls, but insulation cannot solve air flow. It can only prevent heat escape. Let that dominate the conversation through the remaining information.

Insulation and Air Leakage – Unintentional or Accidental Air Movement – Ask your insulator about air leakage. 

Often referred to as draftiness, unintentional and accidental air movement account for a host of undesirable conditions, which can be treated and resolved. Green Attic Insulation has offered comprehensive whole house approach energy audits for many years now.

In the process our our years of case studies, we have compiled valuable information on the variables of creating a comfortable home.  Some simple and affordable fixes, where the treatment plan would be similar for most homes on the block, and complex and seemingly insurmountable problems which took thermal and blower door testing. This being said, we are careful not to place a percentage on energy bill reduction without achieving meaningful improvements to strengthen the air barrier. Air sealing will stop air infiltration. 

What do you absolutely need to know by the time you finish reading this? A stable, healthy, consistent, comfortable , and conditioned living space is the goal.  Treatment of the air flow, heat flow, and moisture flow through the conditioned space are the clear objectives.  Each of these three have a considerably different treatment application; however, some treatments may overlap reducing the movement of one while directly targeting another.

It is essential to break down these three types of movement into their own conversations and separate the diagnosis and treatment of each.  This is a separate but equal conversation when discussing insulation. 

Starting with Air Flow. Also referred to as the “pressure barrier” of the structure, air flow ( unintentional / unwanted air flow ) through the conditioned living space is the cause of over-running the furnace in the winter and cooling system in the summer. 

Air Movement / Air Infiltration Methods  Whole house approach identifying methods of Air Exchange ( per hour)

  1. Wind effect  
  2. Stack effect. 
  3. Combustion and Ventilation 

Insulation and Wind Effect – Think the flag in the yard blowing in the wind. Ask your insulator about wind effect. 

Wind / Breeze  creates a positive pressure on the windward face and negative pressure on the non-windward facing walls, which pulls the air out of the building. Wind causes infiltration on one side of a building and exfiltration on the other. Wind effects can vary by surrounding terrain, shrubs, and trees.

The most effective treatment would be a continuous air barrier around the entire exterior of the home. This is not achieved with more insulation between stud and drywall cavity. 

We find the most vulnerable point of the structure is the seam between the foundation and siding. This can be achieved with exterior caulking or one part spray foam ( depending on the size of the gap and the aesthetics of the building material.

The untreated seams at the foundation level will result in cold first floors around the parameter of the home and cause substantially higher heating costs as cold air is being drawn in through breaks in the pressure barrier. 

Wind defense is often overlooked due to seasonal restrictions. For example, the caulking around the window, doors, facia, and any other seams of the external structure cannot be done when the temps are below 40 Degrees per manufacturer recommendations for adhesion and proper curing. 

So if a contractor meant to schedule the air sealing of the exterior and spring and never got around to returning, the homeowner ( while the home is new and beautiful) has a major air leakage problem, and resulting higher cooling and heating costs for many years to come. 

Insulation and Stack Effect -Think Lava Lamp or Coffee Mug – Insulation ,the mug material, the lid is the ceiling. 

The “stack effect” is warmer air moving upward in a structure. This happens in summer and winter, but is most pronounced in the winter because indoor-outdoor temperature differences are the greater. Warm air rises because it’s lighter than cold air. The rising warm air creates positive pressure above, neutral pressure between, and negative pressure on the lower levels.  Reduction in pressure in the base of the building, forcing cold air to infiltrate through open doors, windows, or other openings. The stack effect basically causes air infiltration on the lower portion of a building and exfiltration on the upper part.

Indoor Combustion and Ventilation – Indoor bath fans, dryers, range hoods, etc 

Mechanical ventilation air movement varies by device, and can cause substantial pressure differences. A common bathroom fan generates between 90-110 CFM ( cubit feet per minute , a cubic foot is about a basketball of air) , while a range hood over the stove can draw as much as 1800 CFM.  These devices must be balanced with air intake or result in unwanted air flow through the building envelope. 

Now having identified three types of air movement / air flow, we can separate treatment of the air leakage by targeting the same corresponding air movement paths. For example, partitions, pathways, and intersections of the exterior to reduce wind movement. In the attic top plates and wall to wall connections are sealed to significantly reduce stack effect.This includes recessed lighting, attic hatch or pulldown stairs.  Openings around flues are flashed and fire-caulked to prevent stack effect though flu clearance framing. 

Together we can ask better questions, raise energy consumption through heat escape awareness, improve ventilation, create healthier homes and happier families.


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I had four attic insulation companies come to my home and greenattic was by far the most professional and thorough with there solution. The sales person David was very helpful in explaining the process. David was also the only sales person that brought a infrared camera heat detector to show me where all my heat loss areas were. The crew that came worked very hard all day and when they finished I was provided with before, during and after pictures so I could see what was done. I had one small issue that was resolved quickly the next day. Great company with great service. Highly recommend greenattic.
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Tim W. 2021
Green Attic

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