Ecological concept: recycling and compliance with various constraints

Renovating is a form of recycling: it's better for the environment than building. Especially when it comes to retrofitting a townhouse, in an already densely populated area, rather than building a house - even a ‘passive’ one - in a former natural area...

1) Expertise and norms

We chose a competent architectural firm : Architecture Vivante in Vannes. For the other service providers, the ability to respect these choices and a local presence were part of the selection criteria.

The standards are very strict for this building in Locmariaquer, which has a number of distinctive elements to respect: the Coastal Act, the Morbihan Regional Natural Park, and is an area close to historic monuments. This means, for example, that the Architectes des Bâtiments de France have to be consulted before the town hall grants a ‘construction permission’ (i.e. permission to renovate). In addition, there are construction standards and the work habits of craftspeople

Not all standards and customs converge: for example, we have not been able to install photovoltaic panels on the roof (even though they are barely visible), so the heating concept (see below) is very efficient, but not self-sufficient. Remuneration of installers based on margins on purchases, and precautions linked to the ten-year guarantee: all this is understandable, but it favours new and over-specified materials rather than recycled and ‘sufficient’ materials: a real problem, which is beyond us...

On the whole, we think we've respected all the rules, our ecological objective... and above all: the comfort of the tenants (and our own!). We're a little over our maximum budget but - shhh, don't tell my wife 😊. We haven't done anything extraordinary, so it's possible to inspire other people with average resources and motivation. Our children are proud of the concept - they'll look after it eventually - and our neighbours seem to like it - they come to visit ( notably on our Open Day).

2) Insulation: respecting facades, RT 2012 standards and eco-friendly materials

This large house had never been insulated or heated other than through open fireplaces (inefficient and therefore emitting CO2 if used in winter). That said, for decades it was simply rented in July-August, therefore underused in mid-season and out of season. But its previous owner had taken great care of the essentials, notably a superb structure and a beautiful slate roof, typical of this town. A slate roof – even if well insulated – is not ideal for the environment: it absorbs solar radiation, heats too much in summer (temptation of air-con) and warms the atmosphere (climate change. Especially sensitive topic on a peninsula threatened by submersion). There is no solution which is compatible with the local style, except my suggestion: let whitish lichens grow there (a field of agronomic research to follow?).

A note on standards? In our opinion, they do not do enough to take into account a) seasonality, by overestimating the importance of winter, therefore with a risk of oversizing the heating, or refusing to renovate because of the cost b) the need for cooling. The best principle for preparing an ecological renovation is to live in the house for several seasons and to observe it carefully. This made it possible to note the strong heat in the attic starting in spring. The challenge of this house was not actually the cold, but the heat.

The facade had to be preserved, so external insulation – which involves extra thickness in the cladding – was not possible. Interior insulation involves several constraints: firstly to reduce the interior volume a little, secondly to cover the interior of the external walls. We chose plaster walls (complying with fire-fighting standards and neutral in emissions), with an 'eco' insulation: wood fiber, typically a sawmill by-product, without chemicals added (except a little bromide salt to limit insects, a traditional product that is not harmful to mammals like us).

The interior walls and the one supporting the veranda do not require insulation. This made it possible to preserve authenticity – retaining period paneling and tapestries – and even to strengthen it – updating the beautiful stone of the load-bearing walls.

The insulation standards applicable have become stringent, which is good. They are calculated on the average for the building - all habitable rooms included. As the rentals will be mainly seasonal, with a preference for using the floors close to the garden, we therefore chose to insulate the ground and first floor more heavily than the attic. This has made it possible to preserve some of the original look, with its wooden roof structure and stone walls.

3) Home heating and hot water: solar and geothermal heat pumps for heating and cooling

Ecological heating involves good insulation (see above), good heat distribution and energy-efficient heating. Several experts helped us choose and size the right combination of these elements. We chose a heating network based on low-temperature radiators, with ‘boosters’ that enable the desired temperature to be reached quickly without overheating permanently. When it comes to producing heat, it's hard to beat heat pumps, which draw energy from nature. Rather than an air-source heat pump ( which is less efficient when the air is cold... precisely in winter, and which makes a lot of noise), we opted for a vertical geothermal heat pump. Three closed loops of pipes pass through holes drilled 80 m deep (duly notified to the authorities, and very sustainable).

An additional benefit of the geothermal heat pump is passive cooling. The temperature of the earth is naturally around 13 degrees (or even a little less after a season of heating and therefore a season of extraction of calories around the pipes]. It is not a question of air conditioning: expensive, bad for the environment and useless in our latitudes. The simple circulation of water below 20 degrees allows the house to be cooled a little, through radiators. In very hot periods, this is supplemented by the circulation of the air, which reduces the perception of heat. All accommodations are 'transverse' from the North-East to the South-West: in often windy maritime areas, this avoids the use of fans by avoiding excessive sunshine. Mediterranean shutters have been installed, which block the sun from above, while providing an opening at the bottom for wind and a view of outside.

4) Transport: bike + electrical recharging

Is it ecological to renovate a house for seasonal rentals? Yes, on two conditions. First, a short season which destabilises a village: our objective is to expand at mid-season, thanks to comfort and communication / entertainment. On the other hand, it is also a question of replacing exotic plane holidays with train & bike holidays in Europe. A complete assessment would compare everything, access transport included, and would be best for a Ty Kabiten stay.

Local transport also has its part to play. The house is close to the centre of the village and to a wide range of leisure and sporting activities, making it an ideal ‘walking and cycling’ holiday for all ages, and for a small additional rental charge.

Come by train to Auray: TGV station one hour from Rennes or Nantes, three hours from Paris, 5 hours from London or Brussels. Then, transfer to Locmariaquer: bus (via the Rond Point du Chat Noir then local Minibus in high season, taxi, or carpool - hitchhiking works well as well).

If you're coming with an electric or hybrid car, you'll be able to recharge it free of charge at the charging points provided in the street-side garden. To avoid involving an oversized circuit, these are simple, slightly reinforced sockets, which allow a full charge overnight (more abundant electric current).

5) Gardens: low maintenance and biodiversity without chemicals

The garden on the street must be able to support vehicles (there is also a parking requirement whether we like it or not), and withstand drought in summer. While avoiding laying asphalt which makes the ground impermeable, and gravel or sand, which abound with weeds or would encourage the use of chemical weedkillers (prohibited, of course). The best method for fighting unwanted plants can be... promoting other plants. We wanted a garden and not a courtyard, or worse: a 'parking'... But there are recycled materials with cells, which support car traffic while allowing plants to grow. This is what we installed, by choosing a mixture of mini-thymes and moss, which resist crushing and drought as well as rain. The old gate with cast iron pillars was widened and reused, removing a wall which blocked the view from the street towards the gulf. This way, passers-by can get an idea of ​​the garden.

The garden on the road is welcoming : typically the gate is open if the house is occupied. An old bicycle hanging in front of the bike shelter indicates its use, and electric charging stations are clearly marked.

The sea-facing garden is natural: it essentially includes a large lawn, and low-maintenance flower beds. The lawn is mowed without noise or smoke pollution, and the grass cuttings are not sent to landfill: by an automatic electric mower. It runs frequently at night because electricity is cheaper and no one is disturbed. By transforming the grass into small pieces which compost themselves and regenerate the lawn, it also avoids having to use fertilizers. At the edge of this mowed area are spaces with tall grass and wildflowers. We do not try to limit 'weeds', other than twice a year by pulling them out and using mulch in the spring and autumn. At the end of the garden, there are typical dune grasses: this precedes access to the coastal path and the small beach.

The garden has a vegetable garden with bins containing various condiments, fruit bushes (raspberries, blackberries, redcurrants), and annual vegetables such as courgette and pumpkins. All this is available for reasonable and free use, for self-consumption by tenants. There is also an orchard with apple and plum trees, and also... space to take a nap in the shade!

The species of trees and plants were chosen from local species, and according to their role. Those far from the house are often honey-producing (helping bees, an essential pollinator for ecology). Those close to the windows often have the property of repelling mosquitoes (also few as near the town, and close to sea water and not fresh water).

The most important natural space in Locmariaquer, has not been altered at all. It’s the sea, the Gulf of Morbihan. Go down to the trail, or take our kayaks, and enjoy!