Working through RT2012

These are the headings on the RT2012 form. 

  1. Administratif. This is where the address, owner details, and the cadastre info relating to the plot along with any third-party project management or architects are listed. 
  2. Surfaces. List the Surface S.RT (m²) and the Surface habitable (m²). The Surface S.RT can be calculated later – just put «à calculer» in the field.
  3. Enveloppe. For details about the exterior walls (façades), ground floor
    (plancher bas) and roof space (plancher haut) . This is all about insulation and how you plan to remove any thermal bridges.  Also any internal floors (plancher intermédiaire). If you have any external buildings (garage, etc.) you should also provide details.
  4. Ventilation. Here there is a list of products you can select from. This section assumes that your house is sealed to the outside and that  
    in order to maintain an ambient temperature in your home you will adjust the controls on your ventilation system rather than open a window. With a GREB house we are not sure this is necessary so have said as much on our initial submission. We stand to be corrected! If it is needed, we’ll be interested in the lowest tech, cheapest and least obtrusive system. The choices in this category are: Couple avec ECS (simple flux), Double flux, and Simple flux.
  5. Menuiseries. Windows. For this section it’s necessary to list the makes and the models along with the Uw values, if available. Also the same info for any doors to the exterior (portes d’entrées).
  6. Chauffage principal. This is for your main source(s) of heat. As I understand it a single log burner is permitted as the main heat source up to a maximum floor space of 100m2. If the house is larger than that additional heat sources are required. Because our current plan is 120m2, we’ve spec’d for electric radiators in the upstairs bedroom and in the bathroom. Whether we put them in or not…
  7. Chauffage secondaire. For any secondary heating systems that will be put in place.
  8. Eau chaude sanitaire (ecs). How will you heat your hot water? There are lots of options (Gas, solar, etc.) but we’ve decided on a thermodynamic boiler, which uses heat from the air to warm the water and is said to reduce water heating bills by up to 80%.
  9. Plan de masse. This is the position on the land showing N-S orientation, surrounding boundaries, etc.
  10. Plan de niveau. This is the floor plan.
  11. Plan de coupe. This is for the facades (north, south, east, west). 

 

Connecting Services

With things moving along it’s time to get our services connected. The seller had to pay the commune £3.5k (per plot – he had two) for the network to be extended past the plot as a condition of getting the CU, so we always figured that was a saving. Unfortunately, although the services are (for a change!) actually right on the border, they haven’t yet been connected: this is the difference between a plot that is sold as viabilised (viabilisé ) and one that is not (non-viabilisé): a very important thing to know before signing on the dotted line!

Saying that, it’s something we hadn’t worried too much about because of all the plots we’ve seen (of which I think only two were viabilisé) we were as close to the services and the road as could be. With the date for signing the act de vente approaching we decided it would be wise to find out – but then we got distracted by revising the planning application in attempt to mitigate the 1.8m foundatio fiasco!

Despite being put off by more paperwork, getting this part sorted out has, so far, been relatively simple. It helps that by drawing up the plans we have everything we need ready to send, so here’s how to go about it.

What services need to be connected?

For any new build you’ll need water, electricity, waste, and a phone line. Of these only the first on is required. If you’re going off grid, you won’t want to connect electricity, likewise if you’re using a septic tank you won’t need waste (assainissement) – and for phone there’s always the mobile network or satellite.

Connect your Building Plot

First steps – get a Devis

The first thing to is to approach the appropriate organisations for a quote – or devis. This is a formal quote which will give you the price to connect your plot. There is information about various sites about standard prices, but only way to know for sure – and the first step in getting connected – is to request a formal devis. Links and info on doing this for each of the services to be connected are below.

Drinking Water (l’eau potable)

For water – which you will definitely need for a straw bale build! – you first have to find out who provides it: in some cases it’s SAUR and in others it’s the local Mairie. In our case, it was the Mairie. Requesting devis in person is no good – you have to put your request in writng, which can also mean sending an email. Here’s a copy of the letter I “sent” (I say, sent because it involved handing it to the Secretary then him reading it) that you can use as a template.

In response I received letter back with the pricing and information about time scales: four weeks from the date of payment.

Waste (l’Assainisiment)

For us this provided by SAUR. If they’re also responsible for your water, you use the same form.

All this can be done electronically (phew!) and they even have a helpful video showing you how it all works.

You first visit their website and download the form:
https://www.saurclient.fr/abonnement-et-raccordement/jemmenage-ou-je-fais-construire/je-me-raccorde

Then it’s time to fill out the form. This is all the information you’d expect: where the plot is, whether you need water AND assainisiment or just one of the two.

In addition, you must provide some supporting documentation:

  • A copy of the planning notice (or a copy of the receipt for having deposited the notice). In our case, because we submitted the permis in the name of the vendor then completed a transfer to our names, I scanned and sent both documents.
  • A location plan, showing where the plot is (street map) in relation to the commune.
  • A plan de masse (also called a plan du projet) showing the cadastre parcel and the location of the buildings to be constructed along with access and how these will be connected to the services. This is a standard document that you were required to submit as part of the the planning application (PCM12), so you will already have this somewhere.

With those three documents and the form in PDF format, you go to this page on the SAUR site and fill out the form. Attach the documents, fill out the CAPTCHA field, then submit the info. That’s it!

Connecting Electricity

This one is work in progress for me. It seems like a very convoluted process (I’ve so far been round in a circle, hence the delay) and is therefore worthy of it’s own post! Once I get somewhere, I’ll update the info here.

In short, your starting point is Enedis.


Photo by Luis Tosta on Unsplash

A 1.8m deep foundation, really?

After receiving the results of the soil study, we had to dig deep in more ways than just into the ground. Was it all over before we’d begun? It took about three weeks to stop panicking. We started reaching out to contractors to try and get prices then we could make a decision. We weren’t signing for the land until mid-September (in the end we signed yesterday) so as that gave us a few weeks to find a quote we could afford – or not, in which case we would have to forgo our deposit and walk away.

After hearing nothing back from any of the contractors who we contacted, we called a builder who we knew from our first 6 months living here. He’d helped us out when we were first looking, had visited some potential plots with us, advised us on foundations there, and even put together a devis for an affordable wooden house! For some reason he wasn’t the first person we’d thought of – but he should have been.

A few meetings later and we had a plan. More importantly, an affordable one. The only hitch was that we’d need to redesign the house. Could we afford the foundation for a single-storey? If so, what size? This guy was so patient! He came out out to the site, bringing along the landscaping guy, and finally we had a quote: just under 30k for the foundation, the driveway construction, and the trench for connecting services. Just over half our budget – but that would be alot of heavy work done which would speed things up for us. Yes, we’d thought we’d DIY this too, but by the time we’ve factored in the time and expense of hiring diggers, laying rebar (after learning how to do it!) it seems the most sensible approach. We really just want to get on with it.

On the 19th September, after much to-ing and fro-ing we submitted a modification to the original building permit. We need to change the design from two storeys to one and make the footprint ever-so-slightly larger.

Here’s how it looks.

The Single-Storey Plan
And the view from the front (with terrace added) in situ.

It’s a big change, but we think that having had the soil study and being put in the situation has done us a favour, for several reasons.

  1. It’s going to be way easier (and faster) to build a single-storey house! The plan is now for the builder to do the foundations and then the roof, so we will build the walls and do all the internal work, but doing it this way saves us time and also costs us less in materials, as he gets discounts we don’t and is only charging for his time.
  2. We were concerned about the seismic safety of a two-storey GREB house and our attempts to find out anything official about it weren’t really coming to anything. We were looking at having to pay several thousand euros for Simpson Ties, to strap the two floors together, which would have been expensive. The only contractor we talked to about seismicity suggested a different method of construction. We have no such concerns about a single storey.
  3. We are less likely to run out of money. The risk with building two floors is that we find out after building the first that we can’t afford to build the second. With a single storey once it’s done, it’s done: roof on and away we go!
  4. Maybe we didn’t need all that space anyway? The thing about having two floors was some of the bedrooms were going to be huge. That’s a lot of space for sleeping in. We justified it on the basis that small children grow up into teenagers, which they do – but at some point after that they also grow up and (eventually) leave home, leaving us with a huge empty house. The single-storey design is as space efficient as can be and, if we need more space, we have half a hectare of land to fill! Plenty of room for small cabins (below the 5m2 threshold for tax, of course :-)) and other outside spaces we can use together. What teenager wouldn’t prefer a “kids cabin” just for them (think sofa and mini fridge) than a humongous bedroom with their parents next door?

There’s still a lot to do but we now have our new plans in and our names on the deeds, so we can start to move forward.

Next steps then:

  • Connect services (water, waste and electricity)
  • Build a driveway so we have access.

Oh, and having decided to go single-storey we went back to the soil study people and asked about the foundation depth. Now all we need is 90cm. Phew! That chops about 5k of the price. Brilliant!

Watch this space!

A man with a geotechnical survey machine

For better or worse, a soil study

With things progressing and our hopes elevated, we decided to go ahead with a soil study before signing. We’ve seen so many plots since this journey began, including:

  • plots that had already been terraced, badly, meaning drainage would cost a bomb.
  • inaccessible plots necessitating two or three pumps to get concrete to the site for a foundation.
  • sites so far removed from services we’d have to blow half our budget just to get water and electric to the site.
  • stunningly beautiful sites in summer, freezing cold in winter.
  • and so on…

This one, the one we want to build on, seemed to be ticking all the boxes. We were optimistic about the soil study and did it really as a formality and for peace of mind, hence waiting until the 11th hour. What we didn’t expect was a result to come back saying we’d need a footing that goes down to 1.8m.

Why? Well, no-one goes down to 1.8m here! The builders we’ve spoken to think it’s mad. The locals we’ve spoken to think it’s mad! Our neighbour (now sadly deceased) built his house himself on a 60cm foundation. Okay, maybe that’s not enough – it is clay after all – but to his credit the house, built with brick ~20 years ago, is still standing and I can say with certainty there aren’t any cracks in it because he never bothered to render it, so there’s nothing to hide.

But you can’t unknow the known. One the one hand we’re thinking, damn, why did we have this done? We could just have ploughed on with a (relatively) shallow foundation and worry about it later – but we wanted peace of mind with respect to the ground beneath. We were hoping for rock a relatively short distance below the clay. What we’ve got is not that at all.

In a future post I’ll write something about the etude de sol process. It was quick and looked pretty simple. The company we used, Sole Terre, work across France and we really helpful and sent out an engineer so we could get our report back before the August holiday, when all of France typically shuts down. He arrived with his van at 6.30am (it was a good job we’d decided to camp on site!) and just got on with it. Then, just 24 hours later, we had our report. Now the journey begins.

As far as next steps go we’re busy trying to get advice on a suitable foundation – suitable being both for the soil conditions and for our budget. This isn’t somewhere we wanted to be with this build – worrying about finishing before we’ve even started – but it is what it is!

This morning I’ve mailed a couple of UK-trained structural engineers who are based in France, so hopefully they’ll be able to offer some practical suggestions and put us at ease. We’ll see.

A 3D image of a house superimposed on a green field, with a line of small trees to the right

Here it is.

Up until now we’ve been using this blog as a “bucket” – to capture information, share it between us, and enable us to find it quickly when we need it. Things have been quietly moving on behind the scenes, so I think we’re at the point where we finally have something to blog about. Let’s begin!

We started this as the planning stage. When we found the land and discussed the purchase with the owner, the CU had six months left to run. We wanted to put a clause suspensive in the compromis de vente to say that the sale would be null and void in the event that we weren’t able to get planning permission. The owner checked with the notaire, who suggested we apply for planning permission in advance of progressing the purchase, so that’s what we did.

Now, almost a year on, we’re almost at the signing – and paying stage. Planning permission was obtained in February and (due to unforeseen Brexit-related events causing a two-month delay in our plans) the compromis was finally signed in June.

This means we’re in the last stages and we should at last be able to use the land, to progress our build.

There are two things going on. First, the sale is going through the usual administrative process, which means consultation with SAFER for the agricultural portion. Second, the etude du sol will be conducted in July and the results hopefully sent in August. This means we can plan (and cost) our foundation. We have a budget of 10,000 euros for this. Will it be enough!? We know that the land is clay and our DIY evaluation (involving a jam jar and some water) suggests it’s up to 90% clay, which is great news if we decide to go ahead with a “traditional” mud render.

And that’s the biggest decision we’re in the midst of. The big question that hovers over us now, is to GREB or not to GREB? More on that soon.

Find out about Seismic Risk

In France, there is a useful database that you can search to find out about the level of seismic risk for your commune.

First choose your region(click the map or select from the list) and then drill down to find your commune.
http://www.planseisme.fr/spip.php?page=didacticiel1

This is the info that comes up for our commune:
http://www.planseisme.fr/spip.php?page=didacticiel4&code_insee=11303&zone_id=3&classe_bati_id=II_MI&nature=N

There are some FAQs on
http://www.planseisme.fr/-FAQ-162- and also a bunch of other info there related to construction – though of course no detail!

There is some more general info about seismic and other environmental risks on this http://www.prim.net/seismes/

Green Energy Suppliers in France

One of the requirements of RT2012 is that all new builds must include a solar-power element. This can mean investing in micro-generation system for your own land or property, choosing a low-carbon, low-energy heat source as your main form or energy. But there is also a third option, which is great for those of us who are on tight budgets. That option is to commit to using an energy supplier that obtains at least 50% of their energy from green sources (solar, wind, water, etc.)

So how to find these? 

There’s quite a list in this article here but also this recent article which gives an overview of Greenpeace’s assessment of the main suppliers in France. Looking at the two lists I would think that you could pass RT2012 by signing up for EDF’s green tariff but according to Greenpeace you’re probably being greenwashed and unlikely to be actually buying energy generated from renewable and non-polluting sources.

One of the companies I lik the look of is https://www.ilek.fr. There’s also https://www.enercoop.fr, which also has non-capitalist credentials. Enercoop has a similar feel to Green Energy, which is the company we used in the UK and is also a cooperative. 

You might be thinking well, how green is it really to be buying energy from a company, but this recent article from the Centre for Alternative Technology suggests that connecting to the grid is a better solution than going off grid. It’s worth remembering that all technology has an environmental cost. Also, if you are generating energy that you are contributing to the total amount of green energy that is available for sale to others who perhaps don’t have the means to invest in solutions themselves. If green electricity is flowing in, the demand that needs to be met by dirty energy (and in that I include nuclear) is reduced. Which also feeds into this article about how being green has become something we do (and get to feel smug about) on an individual level when really collective action is needed.

There’s more info on packages with suppliers for auto-consommation (self-generation) here

Ilek seem to have a comprehensive calculator on their site, giving info on expected payback times and also taking government grants into account.

RT2012 Recommended Boilers (Thermo Dynamic)

For RT2012 one of the ways around having to have expensive solar solutions is to fit a thermodynamic boiler.

This one on Mano Mano is 1.5k euros and may be what we need. 

According to one green energy site they reduce the annual cost of heating water from 350 to 80 euros for a 4-person house.

https://www.manomano.fr/chauffe-eau-thermodynamique/aeromax-4-vs-270-l-thermor-296061-519359?model_id=519359


This comes on the list under ventilation…

This might be one? https://www.atlantic-climatisation-ventilation.fr/ventilation/chauffe-eau-thermodynamique-sur-air-extrait/aquacosy-av/aquacosy-av-100l-et-200l
2035 euro


How thermodynamic water heaters work