Silver Spray is currently (April 2011) a 2 bedroom bungalow on Droskyn Point in Perranporth, Cornwall.

The plan is to replace the bungalow with a larger but ecologically biased house.

I’m very conscious that the term ‘eco house’ is nonsensical.

The best way, from a housing perspective to be sustainable or ‘eco’ is to move to an existing building in a large city where mass transit of people and goods makes places like New York the most per person carbon footprint low you can find in the US. Then get rid of your car and shop for goods (including food) that’s all grown as close to you as possible (‘food miles’).

Having said that, I can make sure that the materials, construction concepts etc. make the construction have a lot less of an impact, during and post construction than otherwise possible.

Ecological / Sustainable House Objectives:

  • Consider the options. What materials, what building methods, what solutions so that the build and end house uses, where possible and sensible:
    • Less waste during construction
    • An efficient end house in terms of energy and water use
      • In the Green Building Bible book there are these rough figures:
        • 100 units of energy in fossil fuel, gives 38.5 units of energy into the grid. Transmission and distribution has loses of about 3.5 units. So, 35 units to a house, of which 13 lost through inefficient use. So 100 units of fossil fuel delivers 22.
        • Suddenly the efficiency of solar panels etc. doesn’t look so bad !
    • Lower embodied energy
    • Lower negative environmental impact
    • Renewables (use recycled materials and materials that can themselves be recycled)
  • Carbon neutral (if possible), defined as zero net emissions of carbon dioxide (CO2) from all energy use in the home, over a year. eg the amount of consumed electricity (from the grid) is less than put back into the grid from PV’s (Photovoltaic solar panels).
  • Look at what gets a property to Level 5, and possibly level 6 ranking on the UK government Code For Sustainable Homes (CFSH).
  • Super energy-efficient.
  • Low construction carbon footprint
  • Low embodied energy (so min steel, concrete, but max wood and other natural materials)
    • But, would timber frame mean a house that moves more in the exposed site, and so potentially damages the air-tightness of the house Vs more steel (where the steel joists are potentially long term recyclable).
  • Natural materials (eg paints)
  • Light, bright and well ventilated (which is likely to involve a mechanical heat recovery ventilation system)
  • Look at aspects of  the German Passivhaus standards, which will mean an “extremely airtight building envelope” and a “heat recovery ventilation system”.
  • Double and triple glazed windows with exceptional good U-values for the windows (including the frames).
  • Solar thermal heating for water for the hot taps (I suspect the site means ground source heating won’t be practical).
  • Under floor heating as the temp the water needs to be at for this to work is a LOT less than the temp for water in a radiators heating system. Or will the house be so well sealed that under floor (or any other) form of heating won’t be needed ?
  • Water capture from the roof + grey water system
  • Have lower water use devices (See www.homebuilding.co.uk/feature/eco-solutions-1)
  • The site isn’t on mains sewage, so the best eco biased system for this.
  • The Housebuilders Bible covers Green Issues from page 346.
  • Insulate more as opposed to less.
  • Build well and build airtight – going for
    – see  www.homebuilding.co.uk/feature/eco-solutions-1
    – SIPs tend to give better insulation and airtight values than on-site build.
    – I want to put in a mechanical heat recovery ventilation system.
  • Lower energy lighting – (See www.homebuilding.co.uk/feature/eco-solutions-1)
  • Sustainable, high quality materials – (See www.homebuilding.co.uk/feature/eco-solutions-1)
  • Also read www.homebuilding.co.uk/feature/eco-solutions-2

Appliances to be enerating the most CO2 by 2016?

I’m not sure I’ve got this right, but I think the http://www.nhbcfoundation.org/Researchpublications/Energyefficientfixedappliances/tabid/518/Default.aspx post means that a 2016 built house (if to the regs !) will have the main areas of CO2 emmissions in order of magnitude as:

  • appliances (49%)
  • space heating (22%)
  • water heating (11%)
  • pumps and fans (10%)
  • lighting (8%)

So I’d better get those best rated appliances and building control systems for the kitchen and elsewhere.

 Personal Life Style House Objectives:

  • An adaptable building that can cope with multiple evolving users – eg young and old, different activities etc.
  • Large open plan living area on the ground floor overlooking the sea view.
    • The living area should capture light from behind the property (the south)
    • Downstairs kitchen, loo, utility (wet?) room
  • Sheltered outside area to the rear of the property for when windy at the front.
    • The rear of the property is south facing for more sunlight.
  • A home office that is in some way conceptually disconnected from the rest of the living space of the house. But for the office to have a sea view.
  • Master bedroom with en-suite to have a sea view.
  • Utility room with washing machine, coat, wellies etc. storage. Be good if this could also be a cold weather drying room.
    • If this room could be switched on and off from being isolated from the ‘heat recovery ventilation system’ that’d be great. So can open windows to create a fresh air flow through the room to help dry clothes etc. Or would the ‘heat recovery ventilation system’ anyway be pulling air from this room, with it’s moisture and pushing back in heat exchang “warmed” and “dry” air ?
  • Outside shower for post being in the sea.
    • Thinking about this. Make it a double shower (2, side by side. It’s often more than one person coming back at once. Needs to have a shower head on a flexi cable to rinse of sand (so a sand trap), clean dogs, shoes, boots etc.
  • Good outside access to storage for sports equipment (canoe, stand up paddle boards, kitesurfing equipment, surf boards, boogie boards, camping gear, van camping gear etc.)
  • Min 2 spare bedrooms.
    • Possibly 1 spare bedroom to be in  an L shape moving back from the main square block of the house, this to have a bedroom with an en-suite and it’s own living area.
  • In terms of design style this site has a few interior and exterior look and feel galleries and I have a growing folder of the same torn from magazines etc.
  • Possible lower the front of the house.
  • Rear (south) facing solar panels. Perfect angel in Cornwall is apparently 30 degrees.
  • Garage / outside storage.
    • If the garage and storage is at the front (sea side) of the house, the space would also be below the house height for rain water harvesting storage and a domestic sewage treatment plant (the property does not have a mains sewage connection).
    • Storage at the front of the house at street level would be convenient for surf boards, stand up paddle boards, canoe, kitesurfing boards and kites being grabbed for the beach.
    • A garage at the rear would be more sheltered from the sea air for items (including my car/van) that rust.
    • Rear parking area for visitors would seem to make sense.
  • Other external items:
    • Wood store
    • Wormery – they like some shelter in the winter. Which could be into a garage.
    • It’d be good to have hooks to hang a hammock at the front of the house and potentially in the sun trap rear courtyard.
  • Other internal items:
    • Integrate sub floor tubes to run speaker cables from obvious spots for the stereo and for the speakers.
      • Also consider doing this to spots in the garden / exterior for exterior speakers.
      • Tubes could go in the walls, ceilings and not the floor.
    • Run a tube from the wall where the media source is likely to be (so maybe from more than one spot) to a ceiling location for a possible ceiling projector. Make sure this location also has a power socket for the ceiling mounted projector. Make sure this tube is wide enough for an HDMI & audio lead.
  • Look at the levels with regards how much people walking on the road below the house can see into the house.
    • Look at a mix between the front wall height and potentially extending the terrace out to the front of the living area, so that it blocks some of the view into the house from people walking on the road in front of the house.
  • Good between room sound insulation.
    • The Housebuilders Bible details sound and thermal insulation measures from pp 172. Also see pp 400.
    • Between the floor levels.
    • Between the rooms.
      • The shared room between the 2 sea (north) facing bedrooms could have extra sound insulation on that shared wall.
      • Possibly put an accoustic door-set, for the door between the landing on the 1st floor and the bedroom off this (to the south / rear).
  • Put meter boxes where they don’t get seen every day. eg The W face of the building, where their is going to be a rarely used alley. This could be at the rear ground (bedrooms floor) level or the main living level.
  • Build a safe into the house. It’s cheap and easy to do this at the build stage.
  • Wine rack. In general somewhere in the house that is temp stable. This could be below the stairs, depending on how they work out and how / if this area becomes a dog bed area or not.
  • Make sure their are wall / room light switches linked to sockets for lamps.

Look and Feel

  • From my magazine tear outs and Web bookmarks, I have a bias towards a modern look that includes flat white render, glass and wood cladding.

See the materials page

Current Buildings on the Site

The 2 bedroom bungalow is the last remaining pre war building at this end of Tregundy Lane.

All other buildings have been removed and replaced or extended in the last 10 years or so.

Although there has been some building modernisation in the form of some double glazing, most of the building is dated and a long way from current sustainable building objectives. For example, there is no central heating and there are visible cracks where some of the building is pulling away from other parts that are subsiding.

A key objective is a well insulated and sealed building that scores high on the goverments code for sustainable homes (CFSH). This is not going to be possible if the curent building is included in the new building.

There is a more recent block built, flat roofed garage to the rear.


Recycle the current building

We do plan to retain some of the stained glass windows so that these can be made incorporated into internal visual features of the new building.

We hope to re-use some of the existing floor boards for furniture. Some of which will stay in the new property.

We will be looking at other material that can be re-used or otherwise recycled into this or any other properties.

  • One of the double glazed windows has already been earmarked for a friends house.