Posts Tagged ‘air tightness’

renewable technologies

Daly preferred technologies – Ryan’s Expert View

A guest blog from Ryan Daley of Daley Renewables – we’ve worked with Daley Renewables on a number of projects, so he’s well worth listening too!

The Daly Approach – How best to spend your money?

At Daly we specialise in a number of heating, ventilation and renewable technologies all designed for new and existing domestic and commercial buildings. We get lots of enquiries for various technologies but in some cases, we see prospective clients focusing on technologies that may not be best suited to them.

This Blog will aim to shed some light on the best approach people should take when designing and building a new home with a view to incorporating various heating and ventilation systems. From 1 to 7 below this is the ranking we have placed on the importance/ relevance of all the areas/technologies we are involved in.

 

1.Insulation and Air Tightness

Over the last 10 years we have seen numerous approaches to insulating and applying air tightness products to new homes. Some of these have been exemplary and some have been incomprehensible. We would advise going with an architect and builder who are well schooled in this area and can provide intricate detailed drawings on how they will make your home airtight. Make sure all this detail is on your working drawings before you go out to tender. In some cases, we are happy to provide our recommended airtightness specification if we are your chosen heating & ventilation contractor before going out to tender. Making a home airtight is not rocket science and is the foremost step in creating a low energy home. We have had clients in the past spending thousands on the best triple glazed windows on the market and not aware that they should have the frame taped to the block/ timber frame. Going with a trusted timber frame company is safe bet as they will guarantee a certain air tightness result for your new build. See photos below of some good and bad examples we have seen over the years!

Good Insulation
Good Airtightness
Poor Insulation
Poor Insulation

2.Ventilation System

“I have not budgeted for this. I will just open the windows to get some fresh air”. That is fine. We have no issue with doing this. But…..Why put 150mm insulation in the floor, go triple glazed windows and have a 200mm cavity wall to keep heat in and then shoot yourself in the foot by having to open the window to let fresh (cold winter) air in?! Put simply if you are not going down the route of a good mechanical ventilation system we would say what is the point of having great insulation, air tight tapes etc. Click here to read our blog on various options for ventilating your home. You are encouraging the risk of condensation and mould growth without a constant change of air. Here you can read a blog from our suppliers’ website and it is well worth a read to find out the merit of effectively ventilating your home.

3. Underfloor Heating

“It is hard to control, we can never get the temperature right and we have high oil bills”. Underfloor heating has had mixed reviews over the years and rightly so. At Daly we understand how the system should be designed to ensure the home is heated to a constant comfortable temperature at extremely low running costs. In our experience we have seen low temperature underfloor heating systems being installed with high temperature gas and oil boilers and if the incorrect controls are adopted the home owner can end up confused on how best to run it, how to set the controls and can have temperature overshoots forcing them to panic and turn the system off. The key for us is that the smart control is all done for you with our intelligent weather compensated controls (we use an outdoor sensor to monitor the outdoor temperature and adjust the flow temperature to the underfloor heating system) which means customers should never have to tinker with the controls. The correct level of heat they require is there for them 24/7 and they do not have to fiddle with controls in order to achieve this.

4. Heat Pumps

At Daly our specialist subject is heat pumps. We understand how they work and we are very passionate about their benefits. A heat pump will give you the lowest running costs over any other heating system as it gets 75% of it’s energy from the surrounding ground or the air outside in the case of air source, making them 4 to 5 times more efficient than a gas or oil boiler. We find that clients choose to go for this system because they understand the technology, they understand that they will be living in a house with very low running costs for the lifetime of the house and they have a house which is very comfortable to live in and which has hot water on demand, all with virtually no maintenance. By doing all the air tightness and insulation measures you are creating a low energy home and a low temperature heating system will be suited
perfectly to this type of building, especially if you have underfloor heating which is a low temperature heat emitter. The both systems combined are a perfect fit. You also will only have one Utility Bill, electricity, meaning less bills to pay plus you are safeguarding against future oil price spikes. With the electric vehicle market building fast momentum, a heat pump will fit in nicely in the all-electric world which we are headed towards, where more power than ever is being generated from renewable resources. The 8th June 2017 was a momentous day in the UK as renewable sources of energy generated more electricity than coal and gas for the first time. Without any grant assistance heat pumps will have the quickest payback over any other renewable technology.

5. Solar PV

Solar Photovoltaic Systems works by generating electricity from panels (typically 14 or 16) on a roof or ground mount frame from DC power which is used in the property after an inverter is used to convert the power from DC to AC. An average system will generate 3,300 kwh per annum. If all of this is used in the home this would save £502.00 each year (based on electricity price of £0.145p/kwh + 5% VAT). Similar to heat pumps, they require little if any maintenance which is a major benefit to the system. With the battery storage market on the horizon the dawn of self-consumption and zero energy bills will be here in the not too distant future. Our Ecoforest ground source heat pump suppliers are close to launching a very innovative product, their E System, which will automatically trigger the heat pump to come on to produce heat and hot water when there is excess energy being generated from the PV System. When the heating and hot water system is satisfied, it will then offload the solar energy into an incorporated battery to be used for the other domestic appliances in the house. The benefit of this is that the battery lifetime will be longer as the heat pump electrical energy is not coming from the battery as it gets first priority.

6. Solar thermal

Does it still have its place? We have seen the first hand the benefits of this system but are conscious of the design considerations. The correct sizing of a solar thermal system is vital to the efficiency and longevity of the system. Free hot water (up to 65 degrees during summer months) for showers and bathing for 6 to 7 months of the year means that customers who opt for this system never regret having it installed.
With Solar PV Systems having increasing demands from our modern homes with the onset of heat pumps and electric vehicles, there may be less time to heat up our all-important hot water for showers! This is where the solar thermal panels (typically 2 panels) come in to their own. Even having it taking the chill out of the water in the Winter means the Solar PV system, which is producing less power during these months, has more time to dedicate to the domestic electrical appliances in the home without having to worry about heating water.

7. Central Vacuum Systems

Central Vacuums complete the healthy living environment cycle. On top of the bonus of spending 30-40% less time vacuuming, the dust that is removed greatly alleviates symptoms of asthma or allergy sufferers. It works by removing dust and exhausted air to the power unit, stored in your garage or utility room so that it is not re-circulated in the home. Not essential to have but can you imagine hoovering without having to lift even a Henry around the house. Ahh….

 

What You Need to Know About Spray Foam Insulation

What You Need to Know About Spray Foam Insulation

SPRAY FOAM INSULATION: WHAT YOU NEED TO KNOW

Spray Foam Insulation: The Essentials

Although spray foam insulation has been in use since the 1940s, primarily for aircraft, for the past 30 years, continual product innovation has seen the increased adoption of spray foam insulation in residential and commercial construction. The rapid growth of sprayed foam insulation in building construction, thanks in part to its immediate and long-term benefits, has allowed the insulation material to sit confidently alongside traditional insulation types in providing thermal comfort for building occupants.

But what is spray foam insulation?  Are there different types available for different applications? And, how does sprayed foam insulation address the latest building codes while anticipating any changes to the building code? In this post, we explore the fundamentals of insulating foam and more.

 

What is spray foam insulation?

Spray foam insulation, also known as foaming insulation or sprayed insulation, is a two-part liquid insulation material(link is external) that insulates and air seals wherever it is applied. The material comes in two large 55 gallon drums – an iso and a resin. These two liquids are kept separate until applied at the jobsite by a qualified, licensed spray foam installer. The two liquids travel up through a heated hose to the spray gun where they are combined to create the foam. The foam expands within seconds to fill the cavity surface.  Depending on the type of sprayed-in foam insulation used, closed-cell or open-cell, the foam expands between 40 and 100 times its size upon application.

Open cell spray foam insulation is ideal for interior use

The types of spray foam insulation

Product innovation over the years has seen the introduction of several different types of spray foam insulation. Primarily in residential and commercial construction, open-cell and closed-cell spray foam is used while high-density spray insulation is used as roofing foam in commercial or industrial construction. Open-cell sprayed-in foam insulation, a soft low-density material, is typically used for interior applications such as wall cavities, underside of roof decks, attics, basement walls and crawlspaces. The open cell structure of low density foamed insulation allows for moisture permeability to help contribute to moisture management and bi-directional drying of the wall assembly.

Closed-cell spray insulation, a rigid medium-density material, can be used in exterior applications such as continuous insulation applications, as well as interior applications. This type of foam insulation has a higher R-value per inch making it also suitable for small areas that require the highest possible R-value to meet building code requirements. Closed-cell spray foam’s rigidity help reject bulk water making it a recognized flood-resistant material by FEMA(link is external).

The benefits of open-cell spray foam

As mentioned, open-cell foaming insulation is best suited for interior applications/house insulation, offering an array of advantages of traditional fibrous insulation materials. Benefits of open-cell foam insulation include:

  • Allows for bi-directional drying
  • Can accommodate long-term creep and seasonal movement
  • Can be installed at a significantly lower cost and target the same specified R-value*
  • Is not considered a food source for mold
  • Provides sound dampening qualities, ideal for use media or theater rooms
  • Lower installed cost, per square foot

The benefits of closed-cell insulation foam

While open-cell foamed insulation has many benefits over traditional insulation types, closed-cell sprayed-in insulation goes beyond to offer additional advantages.  Although closed-cell sprayed insulation foam has a higher per board foot cost, there are benefits that the material offers including:

  • Ability to reject bulk water (closed-cell foam insulation is recognized as a flood resistant material by FEMA(link is external))
  • Can be applied at very low temperatures (as low as 5°F)
  • Adds wall racking strength as well as impact resistance
  • Higher R-value* per inch  – easier to accommodate high R-value* requirements in narrow spaces
  • Lower vapor permeance (can be a Class II VDR)
  • Higher tensile and bond strength

Closed cell foam insulation can reject bulk water

How does spray foam insulation R-value compare?

R-value, the thermal resistance measure of insulation, varies between all insulation products whether they are fiberglass, cellulose, open-cell spray foam insulation or closed-cell sprayed-in foam insulation. Generally speaking the rule of thumb is the higher the R-value, the greater the insulating power.  Focusing on spray foam insulation materials, there is a difference between the two main types. According to industry publication, Fine Home Building(link is external), the R-value for open-cell spray foam is between R-3.5 – R-3.6 per inch. However, there are open-cell spray foam insulation products actually offer R-3.7 per inch such as Icynene Classic and Icynene Classic Max. The open cell structure of low density foam insulation means the R-value is lower than its closed-cell counterpart. Nevertheless, open-cell spray foam does offer superior and consistent thermal insulation and air sealing properties.

In regards to closed-cell sprayed in foam insulation, R-value can range between R-4.9 to R-7.1 per inch. Closed-cell insulation products, such as Icynene ProSeal, allow builders and architects the ability to achieve R-21 in a three inch pass. Innovations such as Icynene ProSeal LE allows for an initial pass of five inches (5”) to achieve R-35.

Spray Foam Insulation & Global Warming Potential (GWP)

Global warming potential (GWP), as defined by the EPA(link is external), is a measure of how much energy the emissions of 1 ton of a gas will absorb over a given period of time, relative to the emissions of 1 ton of carbon dioxide (CO2).  Spray foam insulation products that use water as the blowing agent – typically open-cell foam however Icynene’s ProSeal Eco is a 100 percent water blown closed-cell spray foam – have a global warming potential of 1, the lowest possible number.  This is because water in the mixture reacts during the application process to release carbon dioxide and heat. The GWP of the blowing agent is that of carbon dioxide. Carbon dioxide has a GWP of 1.

A major part of the innovation of spray foam products over the last three decades has been the evolution of blowing agents. Blowing agents are the gases used to expand the cells of foam plastic insulation and give it additional insulating properties. Closed-cell spray foam products typically use synthetic compounds as blowing agents because:

  • they offer improved insulation performance
  • their longer molecular structure migrates out of cell more slowly
  • the closed structure of closed cell foam restricts gas loss best

Today’s “third generation” of blowing agents have a GWP of 700 to 1000 which is still remarkably high considering water/CO2 has a GWP of 1. However, innovation from some chemical manufacturers like the Chemours Company have introduced the next generation of HFO blowing agents such as Opteon 1100, which significantly reduces the GWP impact when using closed-cell spray foam insulation products.

Spray foam insulation and global warming potential

Using SPF to address various IRC Building Codes

While the immediate and long-term performance attributes, flexibility of use and various types of foaming insulation make a strong case for using the insulation material in residential and commercial construction, how does it address the ever-changing building codes?

Today, each of the 50 states follows a different set of building codes making navigating these codes confusing, particularly for architects or builders that have projects in multiple states. In some cases, the building code changes significantly between the state and certain cities or counties within the state. For example, at the time of writing Arizona had adopted the 2015 IRC Building Code, however, Phoenix was on the 2012 IRC, IBC and IECC code. With the majority of states either on the 2009, 2012 or 2015 code, below are some high-level points to consider and about how spray foam insulation contributes.

  • 2009 IRC Building Code
    • Houses built under this code are required to be 15% more energy efficient than the 2006 Building Code.
    • Prescriptive requirements call for higher insulation levels in most building elements in virtually every climate zone.
    • This is the first code that prescriptively calls for a home to meet a defined air tightness standard, though no testing is required.
    • Visual inspection is required for all areas of the house that need air sealing and thermal insulation spray foam can typically attain 8-9% of the needed energy reduction by sealing the house in hard to reach areas.
  • 2012 IRC Building Code
    • House built under the 2012 Building Code are required to be 30% more energy efficient than the 2006 Building Code.
    • 2012 Building Code also requires higher insulation levels in many climate zones and introduces “continuous insulation” requirements on the exterior walls in several colder zones.
    • Homes in Climate Zones 1 to 2 must have an Air Tightness 5 ≤ Air Changes per Hour @ 50 Pascals while homes in Climate Zones 3 to 8 must have an Air Tightness 3 ≤ Air Changes per Hour @ 50 Pascals.
    • Spray foam insulation easily and reliably achieves 3 Air Changes per Hour @ 50 Pascals.
  • 2015 IRC Building Code
    • The 2015 IRC Building Code introduces the Energy Rating Index (ERI) number as a measure of overall building energy efficiency and sets an ERI target for performance in each climate zone.
    • Spray foam insulation still is considered the most economical method to attain the Air Tightness Requirement of 3/5 ACH and lowest ERI.

Foam insulation as an air sealing material

One of the key differentiators between traditional insulation materials and spray foam insulation is the latter’s ability to insulate and air seal. Foam insulation provides an air barrier to wherever it is applied to help mitigate air leakage from the building. Air sealing the building envelope with sprayed-in foam insulation also helps address moisture ingress to reduce the risk of mold and mildew growth as well as the formation of ice dams in colder climate zones during the winter months.  When you compare foam insulation with traditional fiberglass insulation and cellulose insulation, sprayed insulation minimizes air infiltration, it assists in limiting moisture vapor from entering and escaping the home, which in turn reduces the load on heating and cooling systems. Below is a video that compares fiberglass, cellulose and open-cell spray foam in terms of insulating and air sealing value.

 

 

Spray foam insulation is a complex, but high-performance insulation material, that has helped evolve the category further in the past 30 years to allow architects and builders to advance the way they imagine, design, and construct residential and commercial structures.

this information has been taken from the Icyene Website on advice from our spray insulation  subcontractors One Step Insulation

Should you have any questions feel free to get in contact with ourselves or One Step insulation