Horizontal Cracking

Hola John,

I have a detached villa close to Lliber and have recently noticed horizontal cracks above my windows. In places these cracks extend many metres beyond the edge of the window. Is this a serious problem, what action should I take.




Hi Peter,


Horizontal cracking in external walls above windows is a commen problem in Spanish construction. These cracks can extend all around the property and can usually be seen near the roof and near ground level. These cracks are caused by differential thermal movement.


Most building materrials including walls and beams expand and contract, getting longer in the summer when the weather is hot and shorter when the weather is cold.


Spanish construction regulations require several continuous structural "U" beams to be placed in structural walls, this is to provide lateral stability to the structure i,e hold all the walls together at differant levels.


These "U" beams are filled with concrete and steel reinforcements and act as a safe and level seating platform for the floor and roof beams.


Because the "U" beams are of a solid construction and expand and contract at a differant rate to the hollow blockwork they are sat on, cracks will appear.


The "U" beam is simply sliding horizontally on the wall on which it is sited. There is no cause for alarm, the cracks can be filled and painted if their appearance is unsightly but will appear again when extreme weather conditions occur.


Readers should be aware that I have simply explained the cause of horizontal cracks and not vertical or diagonal cracks, which normally indicates subsidence.


John Phillips (F.I.A.S. F.A.B.E. M.I.B.C.O. F.F.B. M.R.S.H. C.M.W.O.B.O. M.B.I.M)

Construction Buena Vista


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Construction Buena Vista
Urb. Palmeria. Orba 03790


Please call us on


0034 965 577 464 (office)


0034 619 089 281 (mobile)


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Buena Vista Villas s.l.

Urb. Palmeria. Orba 03790


Please call us on


0034 965 577 464 (office)


0034 629 554 561 (mobile)


Or simply click the image above