Insulation for homes. Tony Isaacs Tony Isaacs Consulting

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2 + Insulation for homes Tony Isaacs Tony Isaacs Consulting

3 + Who am I? Worked for Sustainability Victoria for 12 years Worked on inter-governmental committee to develop NatHERS Represented Victorian govt. on a number of SA insulation committees Developed FirstRate House Energy Rating Software Project managed introduction of 5 star regulations Consultant Left SV 5 days after 5 star legislation went through Developed training in AccuRate and FirstRate software Developed responses to Productivity Commission Energy Efficiency report for glazing and insulation industries Regulatory Impact Statements Energy Ratings RMIT Centre for Design and Association of Building Sustainability Assessors Disclosure: I have done a lot of work for ICANZ over the years

4 + But insulation DOESN T WORK! Lets get the controversy out of the way at the start! There was a lot of hysteria around the dumb insulation program good policy poorly implemented. REBOUND: people use the BETTER PERFORMANCE that insulation provides to heat to higher temperatures over larger areas and for longer periods. Little evidence of this in 80s Victorian studies by the Gas and Fuel May be true in households who are living in energy poverty and have insulation installed for the first time International studies show 20-30% of savings lost i.e % effective Studies from a time of low energy prices, pre-greenhouse effect How much you save is up to you!

5 + But insulation is DANGEROUS! My house will burn down! Installing insulation too close to or on top of halogen downlights (or any heat source) IS DANGEROUS. Keep the minimum required mm clearance to heat sources and your house won t burn down. Better still replace the halogen downlights with a more energy efficient type! And/or use downlight covers to stop your insulation becoming swiss cheese. People die putting this stuff in! Not if OH&S standards are followed. And don t install reflective foil on the top of ceiling joists. Not just for electrical safety but also because dust will build up on the top layer and halve its effectiveness anyway. Isn t fibreglass the new asbestos! I m not an expert here, but the manufacturers say that the fibre size is 10 times greater than asbestos and is bio-soluble. There are plenty of other products you can choose if you are still worried. If you are installing yourself follow manufacturers instructions: cover up, wear a dust mask and don t install on a hot day in an attic.

6 + Insulation: how does it work? RADIATION: YOU DON T HAVE TO TOUCH IT TO KNOW IT IS HOT

7 + Insulation: how does it work? CONVECTION: HOT AIR RISES

8 + Insulation: how does it work? CONDUCTION: IRON IN THE FIRE GETS HOT ALONG ITS LENGTH Plasterboard

9 + Why is all this important? Different insulation products affect different heat flow modes BULK insulation (batts, boards, blankets, blown in) primarily affects conduction AND because it changes the surface temperature at the top of the ceiling affects RADIATION and CONVECTION too REFLECTIVE (shiny foils) primarily affects RADIATION AND because it changes the temperature of the surfaces it also affects CONVECTION and CONDUCTION too The amount of heat flow stopped by Insulation is represented by the R Value (resistance to heat flow) The same R value, the same effect regardless of the type

10 + Comparing products ALWAYS check that the manufacturer has their product regularly tested to Australian Standard AS NZS Bigger manufacturers test to this standard regularly and this helps ensure you get what you paid for. BULK insulation reports the R value of the INSULATION PRODUCTS Its pretty much the same in all locations REFLECTIVE INSULATION reports the R value of the building element i.e. the wall, floor or ceiling To compare with bulk insulation you have to take away the R value of the other parts of the building element e.g. bricks, plasterboard and air films in a brick veneer wall generally about 0.3 to 0.5

11 + Comparing products REFLECTIVE IT ONLY WORKS WHEN FACING AN AIR SPACE It is not just reflective. It is also low emissivity so it doesn t have to face the hot side to work. Emissivity of foils is tested: usually 0.03 to 0.05 (0.1 to 0.3 for anti glare) The lower the emissivity the better. When installed in a flat or sloping position it has a lower R value for heat flow up (works in same direction as convection) than heat flow down (works against convection) Gives a different R value in different climates because the amount of radiant heat transferred depends on the temperature

12 + Tips on comparing products REFLECTIVE A reflective product provides about twice the R value for heat flow down as it does for heat flow up! If it is a REFLECTIVE product make sure you are comparing the R value for Heat flow up in a ceiling in cold climates, heat flow down in hot climates Heat flow down in a floor in cold climates, and heat flow up in hot Multi layer foil products enhance the effect of foil The smaller the temperature difference the greater the R value By dividing into layers the temperature difference across each layer is less REFLECTIVE products stop 95-97% of radiation. BUT, that isn t ALL the heat flow there is conduction and convection too.

13 + Tips on comparing products: BULK insulation BULK insulation works by trapping still air in layers or cells and air is a pretty good insulator Cellulose products (made from recycled paper) also have some R value in the material too Different products give the same R values at different thicknesses Generally the more R value for a given thickness the more expensive the product If you have lots of space e.g. a ceiling facing an attic thickness is not critical If you have limited space e.g. a wall choose the product that gives you the R value you need Compressing batts reduces their R value and can pop off wall linings! Remember that loose fill settles over time so take about 20% off the new R value

14 + R value at 100 mm for different bulk insulation types (generic)

15 + Squeezing in a batt affects R value 110 mm batt compressed by 20 mm only has 90% of its original R value

16 + How much insulation? New homes Two ways of meeting regulations: Get 6 stars use whatever R value works for your house Meet elemental standards for walls, floors, ceilings, windows and air leakage. R values are set by the regulations. If your house has a passive solar plan, high performance windows or just small window areas you can meet regulations with much lower insulation R values than the elemental standards allow BUT, lots of reasons for using more 6 stars won t deliver 80% emissions reductions by 2050 The extra cost is small: the installer is already there so you are only paying for a little more material Energy prices will rise well above inflation for the foreseeable future It makes carbon neutral easier

17 + Use as much insulation as you can The Optimum insulation level is traditionally recommended based on the present value of savings and the initial capital cost, but the optimum works out to be a vary broad range

18 + How much is enough? In ceilings: At least R4.0 Note that insulation under an attic roof is less effective than on the ceiling in cooler climates In hot climates there is concern that insulation will stop the house cooing down. This is true BUT, it stops it heating up by more than it stops it cooling down. In existing homes, however, be careful to provide shading to windows as well - especially on the west. In walls: At least R2.0 And it helps in internal walls to unconditioned spaces like bathrooms, garages, walls that back on to attic spaces or subfloor spaces (slit level homes)

19 + Wall insulation depends on what is on the other side of the wall

20 + Wall insulation depends on what is on the other side of the wall Walls facing an attic space should be insulated as if they were a ceiling Wall backs on to ceiling

21 + How much is enough? In floors Depends on the amount of heating and cooling in your climate It lower the amount of heating you need, BUT increases the amount of cooling A subfloor space can be much cooler than in the house so you are blocking off heat loss Under the slab the ground is a cool even temperature in summer Places like Melbourne, Canberra and Hobart R3.0 or more, or waffle pod slabs instead of conventional slab construction In mild climates like Sydney and Perth it depends on the house design and a good energy rating assessor can show you the effects. Generally at least draped foil, but use breather foil to allow moisture to escape. Remember to block ends of joists too so outside air can t get in between floor and foil. In hot climates from Brisbane to Darwin maybe use R1.0 board to insulate subfloor walls or R2.0 for elevated floors not above a sub floor space. Again, check with your energy rating assessor for new homes.

22 + Existing homes Ceiling Insulation Top-up ceiling insulation 70% of the benefit is in the first R1.0, so the economics are not nearly as good. It may be more effective to do other things like install a more efficient heater, cooler or hot water system, but Some governments do provide rebates for this which helps to make it more economic, and If you are able to install yourself it s a lot cheaper, or If you just want to do your bit for the environment go for it

23 + Existing homes Wall Insulation Insulation can be pumped in to the wall cavity About 4 times more expensive than installing in new construction You must block off any way for the loose fill insulation to escape e.g. around wall and subfloor vents and other penetrations and at bottom of wall cavity Tricky for weatherboard walls as holes are drilled through each top plate and noggin Can make a huge difference to heating bills Alternatives If you are replacing even some weatherboards use the Alan Pears method: bulldog clip and string to drag the batt down to the noggin level If you are replacing internal linings is much easier, but can cut a strip at the top middle and bottom to thread the insulation through using the Pears method

24 + Existing homes Floor Insulation Same caveats as new homes: best in cool climates Installing from subfloor in an existing home is the worst job ever! But its amazing what you can do when you need to save the money If you are removing carpet and putting in floating timber floors you could use polystyrene board under the flooring Check with manufacturers on compressive strength of board required EXTRUDED polystyrene is expensive but will likely have strength. And be careful how you dispose if it an end of life! There are some new underlay products with higher R values If you want polished floor boards you are loosing insulation from carpet. In cooler climates this can make houses significantly cooler. Underfloor insulation should be considered.

25 + Installation Can make or break effectiveness Thermal Bridges

26 + Gaps in Insulation

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28 + Insulation Installation Basics Gloves and Goggles Breathing mask Wash after installation Dispose of offcuts responsibly

29 + Installing to AS Main focus of the standard: Safe installation around electric/hot features Elimination of thermal bridging: do not leave parts uninsulated (except for above) Maintaining insulation performance: install dry, protect from moisture, restrain if it will fall out, maintaining sealed air spaces for reflective insulation Manufacturers installation instructions shall also be followed: these are based on and ensure your product performs at its best

30 + Maintaining safe clearance Downlights Minimum 50 mm clearance 50 mm Recently updated was 200!

31 + Downlights Old clearances required by Aust. Standard Note also clearances required to framing! Clearances requires to transformer too!

32 + Impact on R values ofleaving out half a batt around downlights

33 + Impact on R values using downlight covers

34 + Downlight covers Igloo Isoliteguard Efficiency Matrix Basic Mitt Ten Mat FF130 Flanged Loft Cover

35 + Maintaining safe clearance Exhaust Fans Ensure 50 mm clearance from top of insulation to top of restraint Minimum 90 mm clearance Clearance of 50 mm to top of restraint Use a Draft Stoppa too

36 + Maintaining safe clearance Flues Minimum 90 mm clearance

37 + Maintaining safe clearance Electrical Cables Use spacer IF wiring conforms to AS3000 (after 89) and Insulatonis less than 150 mm thick otherwise Consult licensed electrical contractor or electrical inspecting authority

38 + Insulating all the ceiling Insulation to extend 50 mm (minimum) beyond inside face of wall

39 + Insulating all the ceiling Drop ceilings: insulate vertical sections OR continue over

40 + Additional requirements for scheme In practice insulation clearances are much greater than the minimum Leave out ½ a batt per downlight in R3.5 reduces effective R value to 2.1 Leave 50mm clearance per downlight effective R is 3.3 In practice too many areas are uninsulated Leave out 1% of area in R3.5 effective R is 3.1 Leave out 5% effective R becomes 2.1

41 + Edge restraints for loose fill Loose fill requires restraint between ends of rafters Use a batt In low pitched roofs manoeuvre using a broom Can not reduce loose fill thickness without restraint Maintain 50 mm between top of insulation and roof

42 + Bulkheads Heat flows through bulkhead more like a ceiling than a wall So insulate to same R value as ceiling between flat and sloping ceiling sections

43 + Clearance around downlights Common practice to leave out ½ a batt With 20 / 100 m2 reduces R by 40% Maximum 100 mm clearance: Batts: trim Loose fill: restrain

44 + Restraints for loose fill Wrong Right 100 mm maximum includes transformer. Shiny side faces in ANDCHECK NO LOOSE FILL HAS MADE ITS WAY INTO RESTRAINT

45 + Other requirements Insulate over manhole (batt/pillow for loose fill) Level loose fill: May reduce in height to edges Not less than 90 mm thickness, full height within 600 mm providing clearance to roof of 50 mm is maintained Safe access in attic spaces for loose fill Light colour durable joist locator tabs extend 50 mm above insulation Every 600 for 4m from manhole in two directions toward centre of attic

46 + OH & S Follow manufacturers / installation companies guidelines for OH&S Safe handling of materials: proper clothing Use of tools and machinery: follow safe use and operating procedures at all times Working in attics: provide light / breathing masks for dust / kneeling boards / stand on framing / secured ladders / not if too hot!! Care around electrical wiring Working on roofs and at height: VIC govt. laws

47 + Information Resources ICANZ Handbook: icanz.org.au/industry-promotion/tech/handbook/ Sustainability Victoria Insulation and Insulation Installation data sheets: Most state governments have reasonable info resources Your Home (Aus Govt): Manufacturers instructions this is one set of instructions you should read!!!