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Standard sizes for windows, internal and external doors

  • 15-07-2023 2:28pm
    Registered Users Posts: 315 ✭✭

    I'm designing what will be my new house, and I'm trying to designing it with cost efficiency in mind.

    For this purpose, I'd appreciate if anybody can tell me what are the most common sizes for windows (1,2 and 3 elements), internal and external doors (main entrance and back garden ).


  • Registered Users Posts: 315 ✭✭spupazza

    Also another question: what do you reckon would be the bare minimum size for the hot press room?

  • Registered Users Posts: 11,386 ✭✭✭✭the_amazing_raisin

    Are you doing all the design yourself or getting an architect and structural engineer involved?

    Typically they'll have design rules around the sizes of windows and rooms

    A quantity surveyor can also help with this, they'll often have industry knowledge and can suggest things like standard window sizes

    As for your hot press question, it kind of depends on how big a hot water tank you're planning to install and what else you want to use the room for

    Modern well insulated tanks don't really raise the room temperature that much. So the old hot press they was constantly around 30C with just a copper cylinder wrapped in a lagging jacket is a bit of a thing of the past

    So you can look into seperating your hot press and linen cupboard if that suits you better

    As a bit of general advice for hot water tanks, I would install one bigger than you think you need. The reason for this is you'll probably end up installing solar PV panels and a heat pump to be compliant to the building regulations. One thing you can install with the solar panels is a hot water diverter, which basically triggers the immersion whenever you are generating more power than you need

    In other words, free hot water 😁

    There's even heat pumps that can act as a diverter, so even more hot water and even free heating (or cooling, depending on what type you install)

    Obviously how much depends on the size of the tank, which is why I say bigger is better. It also means if you decide to install the jacuzzi tub you can have a relaxing soak without worrying about the electricity bill 😂

    "The internet never fails to misremember" - Sebastian Ruiz, aka Frost

  • Subscribers Posts: 41,590 ✭✭✭✭sydthebeat

    Work to block dimensions (ie multiples of 225mm)

    900 X 1350 would be a typical block opening for an upstairs single bed room.

    The window manufacturers will come and measure the block opes before they begin construction of the windows

    Edit: and obviously you have to work to both fire and ventilation regulations, which will impact the size and shape of windows

    Post edited by sydthebeat on

  • Registered Users Posts: 315 ✭✭spupazza

    I intend to do all the design myself.

    For the hot press, around 250l should be more than plenty. I don't want to use the room for any other purpose. Any extra space left (if there's any) will be used to store towels.

    So the smaller, the better

    Apart from the size of the tank does the hot press need some extra space around (i.e for pipes?)

    The house is a two-storey, does the hot press need to be on the higher floor or can it be installed on the ground floor?

  • Registered Users Posts: 11,386 ✭✭✭✭the_amazing_raisin

    Well done for designing the house yourself, but I would suggest doing the basic layout and then getting an architect to turn your concepts into proper engineering plans

    Relative to the cost of the house it shouldn't add a lot and it's worth having an experienced professional sign off just to make sure you haven't missed anything. It's a lot easier and cheaper to fix any design issues in the design phase than after building has begun

    The hot press is typically upstairs, I believe this is because the main consumers (bathrooms, showers) are also upstairs and if the system is gravity fed then you'll have sufficient pressure to serve those consumers

    It's also below the cold water tank to ensure there's good pressure from the cold tank to the hot water system

    Having said all that, you can just use a pressure sensing pump to pump water up from the ground floor whenever it's needed

    For example my shower are on the output of a high pressure pump in the hot press which ensures they have good pressure

    The flip side is that the system doesn't really work without electricity. You could also have a loud pump running when there's hot water demand.

    For example if the pump served your taps as well and someone gets up to use the bathroom during the night and washes their hands with warm water....well then everyone gets an early alarm call 😬

    If using a pump, it's also worth factoring this into the size of the tank. Hydraulics engineering is the type of engineering that generally has me hiding in a cupboard crying, but as a very general rule more pressure equals higher flow rate.

    So you'll be taking water out of your tank faster. If you have someone who likes long showers, you can find them emptying the entire hot water tank in around 20 mins (I'm speaking from experience, and still waiting on an apology from my wife 😂)

    "The internet never fails to misremember" - Sebastian Ruiz, aka Frost

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  • Registered Users Posts: 7,125 ✭✭✭10-10-20

    OP, good luck architecting this.

    If I can add one comment, place the cylinder in the location which provides the optimal/shortest pipe runs off the cylinder, whether that be upstairs or down. Also look at combi-boilers too and especially at air to water cylinders.