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 FAQ

BRICKS
Why is the newly finished brickwork covered by white stains?
It's probably because of the efflorescence.
It is made up of saline, not to be confused neither with lime draining nor with mortar’s draining and spatters due to carelessness when working and failed protection of the fresh brickwork.
Efflorescence is caused by the salts melted in water that crystallise on the brickworks’ surfaces when the water they are in evaporates. Although efflorescence is aesthetically annoying, it is generally harmless as it does not damage the brickwork’s resistance and it disappears in most cases, within the first year after the brickworks’ realisation.
Efflorescence derives in general either from a mortar that is not specific for unplastered knobbled stones or from the water for the slurry that is not pure, more rarely from the bricks.
If efflorescence, instead of being powder, is adherent, before practising any treatment, we advice you to ask one of our technicians.
How do you clean a newly finished wall?
A good layer cleans the wall while building it.
If, when the work is over, you could see still some mortar stains, it is necessary anyhow to wait for the complete drying of the mortar (at least 3 weeks). After this period you can clean the wall by means of a solution at 5-10% of hydrochloric acid, paying attention to wet the wall to its absorption level before cleaning it; eventually brush it softly by a sorghum brush and rinse. This operation can be repeated but once: if even after the second cleaning the stains persist, we suggest you ask one of our technicians for some advice.
Does the unplastered brickwork require a special mortar?
It is better to use a mortar specifically planned for unplastered technique (generally either whitewash only, o bastard), certified as without efflorescent salts. If some pigments to colour mortar are used, only choose the pigments that do not give way to any efflorescence; measure the pigment carefully to always get the same colour for the mortar.
Is it always necessary to wet the bricks?
Yes
Extruded bricks: they must be wet by watering, and the quantity has to be assessed according to the temperature, the season. Hand-made type bricks: through watering or dipping, it has to be assessed according to the temperature, season, they have to be left suitably dripping before being laid.
How can one protect the brickwork from dampness?
A jutting cover equipped with a guttering is in general enough for keeping pouring rain at bay; at the base it is essential that the brick is never directly in contact with the soil and that the flooring drifts the water away from the foot of the wall.
Which is the maintenance for an unplastered brickwork wall?
An unplastered brickwork wall in general does not require any maintenance for many years.
How do you check the vertical joints' alignment?
Once having performed a test when dry to determine the joints’ position, it is necessary to firmly fix a vertical reference string every 3-4 joints and by every corner, recess, projection or holing; these strings must not absolutely be removed until the wall’s completion.

 

ROOF TILES
Which gradient should a roof made of bent tiles?
The ideal gradient for a roof made of bent tiles is between 30% and 45%, fixing a row every three either through suitable hooks or bronzed screws. Lower gradients are not advisable, as there could be water seepages. For higher gradients it is essential to fix the bent tiles to the lists either through hooks or bronzed screws.
Which gradient should a roof made of roof tiles have?
The roof tiles can be laid with gradients included between 35% and 60%. Over 45% it is necessary to fix a row every three through bronzed screws and over 60% it is essential to fix all the rows.
Is the steam barrier always necessary?
On the contrary the steam barrier has to be avoided. It has to be used if the Glaser diagram of the covering should highlight the possibility of the creation of condensation in the interstices of the internal layers of the covering. In this case the steam barrier has to be placed inside the insulating layer. It is rather convenient, in order to enable the roof to “breathe”, to increase the insulating layer that has to be placed the more externally possible, avoiding the steam barrier.
How is a ventilated covering realised?
An effective ventilation greatly improves the living conditions of the attic in the summer period. It requires the existence of an air space of ventilation that has to be free from obstructions, below the roof tiles, with a thickness for normal pitches of a 30-35% gradient and 7 metres length, not inferior to 5,5 cm. for higher lengths it will be necessary to increase the air space’s thickness. This air space has to be realised by means of a series of lists placed perpendicularly to eaves line, fixed on the insulating layer, on which the roof tiles’ hooking lists will be fixed. The air space must be open both in its lower and upper sides; it is convenient to place an under eaves bird guard; on the ridge it is convenient to fix the ridge bent tiles mechanically either to a trabeated list, or to a suitable ventilation comb, paying attention not to reduce the air space section. Some aeration roof tiles won’t be enough to guarantee a suitable ventilation.
When is it necessary to fix the roof tiles? How are they fixed?
Roof tiles are fixed when the pitch ‘s gradient exceeds either 45% (1 row every 3) or 60% (integral fixing). However it is convenient to fix the roof tiles along the pitch’s edges, where the wind will be stronger.
How long can the pitch be?
It is not convenient to realise pitches that are longer than 10 metres, as otherwise the quantity of water coming from the eaves could cause could cause some seepages, and the channel would not be able to get it, should the pitch be longer, it is advisable to break it by means of an intermediate gutter.

 

   
     
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