Five Reasons Your Home is Too Hot & How to Fix It

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Planning your summer escape to the nearest public air-conditioned space? Hold it right there!

On a hot summer day, is your home unbearably hot? Do you find it virtually impossible to sleep? Do you settle for band-aid solutions like letting your air-conditioner run non-stop while saying that you’ll “just deal with” the energy bills when they come?

Make your home a cool haven! Here are five reasons why your home gets too hot in summer. Also included are helpful tips in keeping your house cool amid extreme heat without the need for extra air-conditioning.

1. Gaining Hot Air, Losing Cool Air


Does your home quickly become hot again as soon as your air-conditioner thermostat switches off?

Draught is invisible and can be responsible for up to 50 percent of your expensive heating and cooling being lost to outside. This can happen through gaps in doors, windows, architraves, wall vents and more. 

What to do about draught: Real Draught Proofing goes beyond door snakes and sticky foam seals. Seek professional, architectural solutions to properly and permanently seal your home. This will help you to control your home’s ventilation and reduce your air-conditioning bill.

2. Heat Coming in via Your Windows

Do you feel the radiant summer heat coming in through your glazing despite having your blinds and shading in place? Are you groping for ways on how to cool a room that faces the sun?

Glass is an excellent conductor of heat, and if your windows are single-glazed, heat will be radiating into your home. This can make it hot and uncomfortable. 

What to do about your windows: Don’t worry, you don’t have to replace your windows. Secondary Glazing (retrofit double glazing for existing windows) is a great alternative to double glazing, it delivers all of the same thermal benefits without needing to replace anything.

Remember to choose a secondary glazing system that still allows your windows to open and close as they did before so that you can take advantage of that evening breeze!

3. Heat Pushing Down from the Roof Space

As your roof space heats up, heat is pushed down through the ceiling into your home. You may even feel this heat building up overhead.

The heat from the sun is stored in your roof tiles and ceiling space. As this continues to heat your home, this stops your home from cooling down overnight and can make it very uncomfortable inside.

What to do about a hot ceiling: Installing a ceiling insulation is the most important action you can do for your home. Many of us believe we have it but often it isn’t enough or it has moved over time.

Consider augmenting your existing ceiling insulation with something that is non-allergenic, moisture, and rodent resistant and maintains its shape long-term.

4.Heat Rising Up From Below

If your home is built off the ground, (e.g. on stilts), you’ll be aware that hot air can build up under your floor, rising up through your floorboards, and heating your home from below.

What to do about heat coming in under the floor: Proper underfloor insulation will prevent heat from entering your home from underfoot. For the best possible results, ensure you use a high quality polyester insulation, stapled firmly and permanently beneath the floor.

5. Heat Radiating Through Your Walls

Uninsulated walls conduct heat into your home extremely easily, especially if you’re in full sun.

If you have brick walls, you’ll know how hot those bricks can become when the sun starts to heat them up. This heat is stored in the brick and continues to push itself into your home making it very hot at night and hard to sleep comfortably.

What to do about heat coming in through your walls: Retrofit Wall Insulation can be applied to weatherboard and brick walls. It is pumped in via a hose to ensure it can be filled to the brim for optimum coverage and effectiveness. This insulation creates a protective barrier between the hot outside sun and a cool and liveable interior space.

Invest in Quality Draught Proofing and Insulation Solutions

Double down on your thermal comfort this by insulating your doors, windows, ceiling, floors, and walls. Not only does an all-home retrofit improve your thermal comfort, but it also lowers your energy cost for the long term as well.

Discover a wide range of draught-proofing solutions for your home that help you grab ahold of lasting thermal comfort.

Know how you can unlock your journey toward a more comfortable home across all seasons, call ecoMaster today on 1300 326 627.

24 comments… add one
  • Annie Frances May 25, 2016, 5:42 am

    My house is incredibly hot for the summertime. I think it might be because of little ceiling insulation. Fortunately, I already called a company to repair a hole in my ceiling. Maybe they can add insulation to the ceiling as well. Thanks for the tip!

    • ecoMaster June 1, 2016, 10:48 am

      Hi Annie, we’re glad you found this post interesting. Just remember to review your options when choosing the best ceiling insulation for your home. We always recommend polyester ceiling insulation because it’s proven to hold its loft (thickness) long-term, which is what will keep your home cool in summer and warm in winter.

      This is another article about ceiling insulation that you may find useful: Ceiling Insulation: How Much is Enough? [CLICK TO READ MORE]

      We wish you all the best in making your home more comfortable, please get in touch if there’s any way we can support you further.

  • Alice July 27, 2016, 1:02 pm

    This article is very informative. There are a lot of factors why your home could be so hot. Insulation can only answer so much.

    • ecoMaster July 28, 2016, 2:10 pm

      Hi Alice,

      Thank you for your comment, you’re absolutely right. There are many things that influence how our homes hold a comfortable temperature and while insulation is extremely important, it’s important to consider draught and glazing too.

      By considering your home as a whole system and creating a prioritised plan, you’ll get the best value for your money and feel more comfortable sooner.

      All the best with making your home cooler.

      Warm Regards,

      The ecoMaster Team

  • Sarah December 30, 2016, 7:55 am

    no wonder my house is so hot. It is in full sun, no ceiling insulation and raised off the ground. Unfortunately I’m renting and the owners are unwilling to do anything about it.

    • ecoMaster January 5, 2017, 11:40 am

      Hi Sarah, Thanks for your comment. We are finding landlords are becoming more amenable to retrofitting their properties as tenants are becoming more discerning about the comfort of the home they rent. Retrofitting is also tax deductible! Regards ecoMaster team.

  • Del February 27, 2017, 9:29 am

    Thanks for the information, exactly what I was looking for, looks like roof insulation is the way to go, hopefully it won’t cost an arm and a leg!

    • ecoMaster February 27, 2017, 10:08 am

      Hi Del,
      When researching insulation, be aware that poor quality insulation is unlikely to achieve a good result for you or your family.
      If budget is an issue, consider adding insulation is stages – using the best quality insulation in the most used part of your home.
      Then covering the remaining areas as budget permits.
      The saddest calls we receive are those with someone lamenting that they used poor quality insulation to save money, but are still uncomfortable with high energy bills.
      Warm regards, ecoMaster team

  • Linda Hunter April 5, 2017, 10:17 pm

    Hi. My home is steel frame with hardie plank. and is sealed so I cannot move a plank to see what is inside. There is supposed to be insulation in the walls but one interior wall that has sun on it all day warms ups and is hot to touch, even my pillows on my bed are hot. If there is insulation in the wall should the interior get this hot to touch making the bedroom stifling. The house is only three years old.

    • ecoMaster April 6, 2017, 9:31 am

      Hi Linda,
      Thanks for your question. I’m not sure of your physical location… if you can drop me an email to [email protected], with that information that would be helpful. For everyone else reading this comment, it certainly does not sound like the walls have been insulated correctly. Hiring an assessor with a thermographic imaging camera will allow you to “see” inside the walls without removing planks or drilling holes in the walls. As the home is only 3 years old, it will still be under a Builder’s Warranty – so you may consider organising a Building Inspector with a thermographic camera to write a report on your home and then take the issue up with your builder.
      If the wall imaging shows you do have insulation, and it was installed to a good standard, I would recommend you look at one or more forms of external shading – such as a slimline water tank/s, (solar) pergola, deciduous shrubs / trees, to stop the sun from hitting that wall. Once the heat is inside your home, it is a much more expensive proposition to remove it. Warm regards ecoMaster team

  • Ricardo May 15, 2017, 9:32 pm

    Hi there,

    I m soon building my own house in the North East of Thailand. There temperatures are very high (can easily reach the 40 degrees Celsius) and it does not get any better during the nights. We have a short “Winter” with temperatures going as low as to 10 degrees Celsius but it takes just a couple of months. What kind of insulation should I give priority to? Walls? roof? floors? all the above? Are the materials of good insulation too expensive?Thank you.

    • ecoMaster May 16, 2017, 9:54 am

      Hi Rick, Thanks for your question. The co-founders of ecoMaster were recently on a 500km 5 day bike ride in Thailand raising money for Hands Across the Water, so we are aware of the temperatures in Thailand! 🙂 The issue for you may be the availability of good quality insulation – we are unfamiliar with the brands available in Thailand, so treat these comments as good principle guidelines.
      In a hot moist climate, we would consider polyester bulk insulation to be a good place to start (see this site for examples of the best insulation available in Australia) for ceilings, walls and underfloors. This is because polyester insulation will not carry mould and will dry out completely, with no damage to the insulation, if it gets wet.
      To further reduce the impact of heat, you should consider including reflective insulation as well. Bulk insulation installed first, then reflective after that (so reflective insulation would need to be outer most facing product).
      If budget is a major issue, do not skimp on the quality. Invest your money where it would be the most difficult to retrofit later – that would be your walls. You can also retrofit insulation into a ceiling when you have the funds available, and then later again under the floor.
      A very important issue for you is the design of your home (research Passive Solar Homes) before thinking about insulation. A design sympathetic to the sun’s orientation will make an enormous difference to the comfort of your home. Another major impact on your home is the ability to get good cross flow of ventilation through your home. Consider where the prevailing winds come from and ensure your windows are oriented so they can pick up that breeze and direct it into, and through, your home. Best of luck with the construction of your new home. Cheers Team ecoMaster

  • Vannesa Rivas June 6, 2017, 2:44 pm

    Thanks for the article, it helped shed some light on what we can do for our house. I just don’t know where to start when I live in a house that is 20+ years, mostly brick, with a high possibility of no roof insulation, and being in the desert land of Arizona.

  • Kevin Cushing June 13, 2019, 12:07 am

    I just got ceiling insulation and the company also did some caulking. The walls have some insulation (though probably not enough) and a double paned sliding glass door is probably old.
    My house is now only slightly cooler and the nights are warmer, forcing me to keep fans on all night. Is there anything I can do without spending thousands of dollars?

    • ecoMaster December 19, 2019, 2:08 pm

      Best check with the guys you contracted to do the works and ask why it hasn’t made much difference. Sorry we can’t help further.

  • shaista babar June 30, 2019, 12:43 pm

    Hi There
    was just wondering how to keep cool in summer..My bungalow was built in 2013..moved in 2014….it is very well insulated therefore roasting ..what can I do

    • ecoMaster December 19, 2019, 2:05 pm

      If it’s well insulated then it’s crucial to adequately shade the windows from the summer sun. Sunlight getting in directly through the glass will turn directly into heat and will be difficult to dispel except with an A/C. If you need something temporary just for summers then try Renshade which you can buy on the ecoMaster Store.

  • mike September 3, 2019, 1:23 pm

    I recently blew insulation in my walls ,have replaced windows. My attic has 2 layers of insulation yet my house is warmer inside than outside with all the windows open and fans on.The only thing I can think is the over hangs are stuffed with insulation not letting my ridge vent work.

    • ecoMaster October 2, 2019, 5:18 pm

      Hi Mike, as we improve the insulation of our homes as you have been doing it becomes more important to ensure that the windows are well shaded from the sun in worm weather. Sun coming directly through the glazing will turn to heat when it strikes anything inside your home. A modest sized high efficiency split A/C system should be able to shovel out that heat pretty easily of you keep the windows closed. Shading is the first port of call though. I hope that helps, Maurice.

  • Tess Lancaster December 13, 2019, 11:03 pm

    I live in a ex housing commission double brick 1950s house with cement walls as well on the In side. Built 1 metre off the ground in height. The house is like a furnuss on hot summer nights and an ice bucket in winter. In the summer in days very cool but at night with no insulation in walls or underneath outside. The roof is insulated twice over the past 40 years just sit on top of each other on roof. I have thick sunblock Curtin’s in all rooms and outside shaded cloth on all windows. Carpet on all floors. The house is a Furness and when liying in bed summer nights I feel like I’m burning from the inside out, it’s crazy. Please help me out with what I can do. My husband was going to I ste the outside underneath with white foam poly carbon sheets the ones used for packaging. Yes I know they are very inflammable but at a cheap way of doing things Ido t know what other option s as this is my home.
    I look forward to your reply.

    • ecoMaster December 19, 2019, 1:39 pm

      Hi Tess, I am familiar with these homes. Your description of “furnace” and “ice bucket” are the usual way of describing homes with limited insulation and potentially somes significant draught issues. Are you in Melbourne? If so I would be interested in doing a case study of one of these homes. Please give the office a call on 1300 326 627 to discuss.

  • Sue December 17, 2019, 6:24 pm

    We are experiencing extreme temperatures here and I just went into the kitchen and thought I had left the gas in because it was so hot where the gas hob is, the heat is coming though the exhaust fan. I have in the very cold weather when the wind is howling through put a bath cap over it and it stops it, I was wondering if I could something similar putting a piece of roof insulation into the batch cap to keep the heat out and then take it off at night.

    • ecoMaster December 19, 2019, 1:36 pm

      Hi Sue, the fan can probably be easily treated by fitting a Draft Stoppa over it from the attic side. You can see these on the ecoMasterstore just by searching “Draft Stoppa”. However, there are probably other places and reasons that your home is not performing well thermally. Perhaps consider if an ecoHome Assessment is an appropriate way to develop a prioritised plan to improve the thermal response of your home.


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