- 1 You have found the ideal land for the construction of your home. Here are some questions to be sure of your land and the dream does not turn into a nightmare ...
- 1.1 1. The land is it clay?
- 1.2 2. Is the slope?
- 1.3 3. Is the heterogeneous soil?
- 1.4 4. Is there a risk of slipping?
- 1.5 5. Is there any risk of collapse?
- 1.6 6. Is the compressible soil?
- 1.7 7. Is there water in the soil?
- 1.8 8. Is there a risk of flooding?
- 1.9 9. Is the rocky ground?
- 1.10 10. Are there any hidden risks?
- 1.11 Good to know
You have found the ideal land for the construction of your home. Here are some questions to be sure of your land and the dream does not turn into a nightmare ...
1. The land is it clay?
Risk: successive periods of moisture (swelling) and dryness (removal) are detrimental to constructions that have not been designed taking into account this characteristic (see inset). You can learn about the ministry's website for Ecology: www.argiles.fr. It identifies risk areas. This information is a first approach for the analysis provided results from the interpretation of geological maps 1:50 000. It is important to verify this presumption of clay soil interviewing the mayor and neighbors. But only a soil study will know with certainty the exact nature.
2. Is the slope?
The slopes have many problems. The foundations of a house built on this type of terrain are embedded more deeply into the ground at the upstream and downstream. In case of drought, the rear foundation is therefore less exposed than those of the opposite side, resulting in a risk of cracking. It is then necessary to descend evenly foundations so they have all the same installation. The slope may require excavation, backfilling or support which increases costs. Today, one often chosen solution is the use of a light structure (wood, metal) resting on stilts. A style not always in line with the local plan.
3. Is the heterogeneous soil?
Another disadvantage on a slope, the soil under the foundations encountered downstream is not necessarily similar to the upstream and therefore may not have the same sensitivity to changes in water or the same mechanical strength, which is very detrimental to the building.
4. Is there a risk of slipping?
A lack of soil cohesion, combined with steep terrain, can cause landslides sometimes result in significant volumes of earth. Trees bent, cracks in the ground at the upstream and downstream ground beads are indicative of a recent shift. If this is the case, the game is not worth the candle. As much wear your choice on another field.
5. Is there any risk of collapse?
In the mountains, there may be a risk of avalanches and rock falls. Inquire at the town hall or the DDE (Departmental Equipment).
6. Is the compressible soil?
The so-called land "compressible" (in the valley bottoms, peat, not compacted embankments) are not strong enough to bear the weight of a house. Although soil always deforms under the weight of a book, in the case of a compressible soil, the extent of the slowdown is greater than what the house can accept. The solution is to adopt a special type of foundations (slab, piles, etc.).
7. Is there water in the soil?
Water is present in the soil in different forms. It may be a water table which descends deeply during dry periods. It becomes difficult to detect. The problem with this scenario is complicated to solve if it was not considered from the start of construction for the basement risks being flooded. As you investigate the neighboring or the town hall. Also note that the presence of water in the soil can make sensitive to frost, particularly in elevation (water expands when it freezes). It will then adapt the foundations.
Water can also be seasonal and fed exclusively by precipitation. It tends to go down into the ground under the effect of gravity and stop at the boundary of impermeable layers. The place names of places is often a clue: Brook Street impasse ponds ... The realization of a drainage or crawlspace may be necessary.
8. Is there a risk of flooding?
The risk comes mostly small rivers can overflow their banks during thunderstorms. Prudence dictates not to build in the floodplains of rivers (spotted on a topographical map), but this rule is often ignored. If your land is bordered by a stream, you must inspect the area to identify potential signs last flood (plants "aquaphiles" on your land, spreading mud or blank areas of vegetation ...).
A flat is not always risk free. A gradient of a few meters can make the difference among a field that will be flooded and another that will not be. You can inquire at the town hall or from the Departmental Directorate of equipment and the neighborhood. You can also find information on the www.prim.net site, under the heading "My face common risks."
9. Is the rocky ground?
When rocky parts appear on the surface, and that the house does not rest evenly on the rocks, there is a danger of instability. On the other hand, the earthworks in the rock can be very complicated and expensive.
Sometimes soils contain invisible underground cavities from the surface. Often these residues from mining or old quarries which we forgot the location. Some areas are known to subsidence caused by these old wells. These cavities can also be of natural origin, carved by water. Services are responsible for identifying risks to urban areas exposed. In Paris, he is the General Inspectorate of careers. When a building permit is filed, it goes through this service which advises. However, in rural areas, all underground quarries are not listed. You can observe the neighboring buildings to look for cracks due to ground movements. You can also inquire at the town hall or from the DDE.
Good to know
The orientation most favorable according to experts: southwest.
The good soils are made of rock or sand and gravel.
Before signing, ask about the cost of connection to public facilities if the land is not serviced. It can be much higher than you think (several thousand euros).
Stuning view" is never guaranteed. A construction can still intervene despite promises from the seller.