Projet de réhabilitation d'un site touristique à N'Demban en Gambie
Bernard / Xavier
Context of the visit
On invitation of Adama Bah and Lucy Mc Combes to estimate the work.
Preamble
In this document for the sake of simplicity, reference will often be made cardinal compass points for reference, with north being on the water tower side.
To differentiate the two buildings involved in the project, the following terms will be used:
- Main building to the north with three rooms to be developed into main and secondary space,
- Secondary building, located to the east, with two rooms, one of which will be fitted out as part of the project.
The present document includes several appendices in which plans and estimates collected from the artisans consulted are proposed.
This document will not deal with the development of the exterior (landscaping in particular).
Findings
General
Roofing
In general, the roofs of both buildings are in a satisfactory condition but require some minor repairs. These include:
- Main building: the South-East and South-West corners need to be redone (see photos)
- Secondary building: sheets visible from the outside are deformed and need to be repaired/replaced.
- Multiple leaks can potentially exist at the fasteners between sheets. They will all have to be repaired.
Termites
As previously mentioned, the presence of termites must be noted in this building: pathways on the walls and woodwork and multiple sawdust discharges along the woodwork (photo above). This observation requires us to verify that the frameworks and various woodwork are free of termites and to treat them preventively.
As it was not possible to verify during the visit that all the structures were sound (free of any insect attack including termites), a complete check will have to be carried out on the occasion of the work to be undertaken.
Floors
All the floors in both buildings are in good condition, have no major defects and can be preserved
after thorough cleaning and possible surface treatment.
Well and septic tank
The following findings were made:
- The camp’s water supply is provided by a borehole in which a pump is installed to draw water from the water table. The water used is not treated.
- The toilet drains converge in a concrete septic tank. The outflow is discharged into a bottomless tank.
- It should be noted that the distance between the borehole and the water treatment system is less than 25m.
- No analysis of the water supplied to the buildings was carried out
Electrical installations
Two independent circuits can be identified from the three-phase feeder point in the office building.
General protection rated at 100A is installed.
As one phase is not used, two phases are used to serve the kitchen and the huts respectively. No power or differential protection is installed on these feeders. (to be checked).
The cross-section of the cables used for these services is 4 mm2 (to be checked).
The cross-section of conductors visible inside buildings is 1.5 mm2 .
Main building
Roof soffit
The undersides of the roof overhangs show signs of moisture and mold in several places (see photo).
It is suggested that, once the leaks that caused this finding have been treated, the undersides should be covered with the wooden panels recovered after the removal of the false ceiling in the main space
Windows
While the glass panes of all the windows are present and in good condition, all the mechanisms are inoperative. They must be repaired or replaced.
Walls
The aesthetic fragility of white walls should be noted. It is suggested that less fragile colours (such as
ochre) be used at the end of the work, and that the door and window frames be created and
highlighted by a lighter border?
Requests made
Fitting out the main building
Organisation of volumes
The premises currently have three rooms accessible from the entrance. It is planned to create two
independent volumes:
- An area to the west that could possibly be divided in two by a movable partition and giving access to a shower-toilet area to be created on the adjoining northern terrace and accessible through a wooden door. This area will be referred to in the following as the « main space ».
- An area to the east, later referred to as the « secondary space », taking the two rooms to the east, the larger one being used as a bedroom, the smaller one for a shower-toilet area.
An entrance hatch open to the outside will be created to allow access to these two independent spaces.
Main area
- A ceiling isolates the living area from the attic under the roof. This ceiling, made of wooden plywood sheets and fixed on a wooden lattice, will be removed in the main space to create an open volume leaving the roof visible.
- A solution for separating the main space into two zones could be to install a movable partition suspended from an existing beam supporting the roof truss.
Fitting of the secondary building
This space currently has two rooms. The one room on the left is being worked on as part of this project, with the room on the right retaining its current function as storage space.
A sleeping area and a shower-toilet area will be created in the part of the building to be converted.
There is a risk that the water distributed to all the premises will be polluted due to the proximity of the extraction forge to the wastewater treatment plant (very likely presence of faecal matter in the water taken and distributed).
Even if the water distributed in the future facilities is not intended for consumption and if the general configuration of the land (slope organisation and proximity of the river) may suggest a favourable flow direction of the water table, it may be recommended to improve the water treatment
system.
To this end, it is recommended that consideration be given to replacing the existing installation with a plastic septic tank that is watertight and equipped with a sufficient number of tanks. In any case, it would be prudent to check the quality of the water supplied to the project.
Roofing treatment
Sealing :
A complete overhaul of the roof sheeting surfaces should be carried out to address all defects, whether visible or not from the inside or outside, in order to limit the risk of leakage.
Treatment of structures :
As mentioned above, it has not been possible to verify that the entire structure is free from insect attack (particularly termites). However, the presence of termites in various parts of the premises requires strict control and preventive treatment.
Ventilation :
As the existing ceiling was removed in the first stage, there is concern that heat radiating from the sheets could contribute to a significant rise in temperature in the living areas. It is proposed that the roof be modified as follows:
- Removal of the current ridge.
- Creation of a sufficient opening to ensure convection of hot air.
- Replacement of the ridge with a folded sheet with sufficient overhang to protect against rain and with sufficient space for convection.
- Interposition of insect protection in the space thus created.
Development proposals
General power supply
A general plan of the electrical installations is given in the annex.
Regarding the power supply inlet located in the office building, it is proposed to protect the two outlets to the kitchen and the living areas with separate protections, each comprising a thermal protection rated at 32 A and a 300 mA differential protection
Main building – Main space
The modification to remove the ceiling (plates and supporting cross-bracing) in the main space will be carried out in the first instance and will allow the actual roof modifications as described above to proceed.
Organization of volumes
(See attached plans)
Several proposals for the development of the building will be proposed below. These include:
- Implementation of a movable partition to separate the main space into two distinct areas,
- Creation of an additional living space above the secondary space
- Proposals for the design of the access hatch
- Design of the shower-toilet area
- Rehabilitation of the external roof undersides
Movable partition :
In response to the desire to install a movable partition to divide the living space in two, the presence of a support beam for the roof trusses would allow it to be hung (see photo opposite).
This provision confirms the need to check that the structure is free from insect attack.
The area shown on the right could be used for a floor made up of beams resting on the lower load-bearing walls and wooden decking.
Access to this space would be by means of a staircase (miller’s ladder type) arranged as shown in green opposite
The project proposed by XXX (in green above) provides for
- the opening of the current wall to create an entrance hatch open to the outside,
- moving the entrance door to the main space,
- its replacement by a window (masonry and mechanism),
- closing the access to the small room in the secondary area,
- the creation of an access from the bedroom to the bathroom in this space.
This project has been budgeted in the attached quotations.
Electrical installations
It is proposed to provide a general electrical panel serving the two spaces of the main building and the secondary building. This panel will include for the main building (main and secondary spaces together):
- two 16 A thermal protections for the main space outlets and the outflow to the secondary building
- 10A protection for the lighting in the main building
- 30mA protection for the main building
The existing lighting and power supply uses the false ceiling. As this is to be removed, it is proposed to replace the existing suspended light points with wall mounted spotlights using LED technology. It is suggested that a warm colour is preferred in the choice of bulbs.
The light points will consider the possible use of a movable partition if one is installed.
Well pump supply
A specific feeder, protected at 16 A and 300 mA, will be created to replace the existing feeder in the secondary space and supply the well pump. Equipment installed in the secondary space will eventually be moved to the general switchboard in the main space.
Bathroom
A bathroom will be created to the north of the main space using an existing slab outside (in red above). The following provisions will be used for this purpose:
- Construction of a masonry wall of sufficient height to leave sufficient open space under the existing roof,
- The space is closed off with a fine-mesh screen for protection against insects,
- Closing with a door that can be retrieved from the secondary space (existing door in the new access chamber) or reversing the opening direction of the existing door,
- Implementation of the above-mentioned equipment (toilet, shower and washbasin),
- Possible light point with control from the main area.
Main building – Secondary space
Organisation of volumes
The plan above shows the alterations that need to be made to make the access and bathroom of this
space independent of those of the main space:
- Condemnation of the existing access to the future bathroom, which currently opens onto the new main access hatch to the building,
- Opening of a new access to this bathroom from the bedroom. This access can be equipped with a door or simply with a curtain.
Electrical installations
The following electrical installations will be provided in the secondary space of the main building:
- Installation of a second socket in the room,
- Changing the position of the bathroom lighting control,
- Possible addition of a socket outlet in the bathroom provided that a 30 mA differential protection is effective.
Secondary building
Organization of volumes
The modification of this building will mainly consist of creating a bathroom. This will include a toilet,
a washbasin and a shower.
Electrical installation
This secondary building is supplied from the main building and is visible opposite. It should be noted that the PVC pipe has deteriorated, revealing the conductors. The visible cross-section of these is 1.5 mm2 , which is not compatible with the installed protection. It is therefore recommended that the conductors between the two buildings be replaced with a minimum of 4 mm conductors2 . It is proposed that: · to interrupt the pathway opposite and bring the conductors inside the building, · install an electrical panel equipped with a 10 mA differential circuit breaker to protect the building, · to use this panel as a distribution box to supply the various circuits in the building |
The interior network of this building (bedroom and bathroom) can be made visible.
Annex 1
Forwarded drawings
Annex 2
Cost estimates received
Note :
Some rates seem low (painting in particular) we believe that the costs will be increased. We’ll surely have extras expanses. Hard to define now.