Helibars are a versatile product used in many applications to repair failed masonry without disrupting the brick work, and Newman’s have become a leading designer and installer of Helibar systems in London and the South East.
We work alongside a large number of commercial fit out contractors in London who often require our specialist Structural Services with a fast turn around and this project in central London was no different.
Newman’s were called upon by a home owner in East London who had discovered diagonal cracking and substantial rotation to the brick arch lintels to the rear of the property causing substantial concern.
With our Head office in Hammersmith, West London a surveyor was able to attend site on short notice to carry out a Structural Survey and diagnose the cause of cracking.
Lintel Failure was diagnosed after the replacement of the original load bearing timber frames which caused the lintel above the frame, supported mainly by the timber window, to drop.
In order to restore the masonry TwistfixBed Joint Reinforcement was installed to create masonry beams within the structure which distribute the structural loads across the masonry and create a reinforced beam alleviating the need for all the lintels to be rebuilt.
In very few instances it is not possible to save the lintel as the damage is to severe and a rebuild is the only option. Luckily for our client all of our technicians are time served in both traditional and modern methods of masonry repair.
Diagonal cracks above window openings and door openings are common structural defects that show signs of movement which will need to be rectified.
Diagonal stepped cracking often indicates that the lintel that supports the masonry above the opening has failed. There are many types of lintels available and in use such as brick arch and soldier course lintels commonly found in period properties. Newer lintels are normally steel Catnic type lintels which can also fail showing signs of diagonal cracking above the opening.
In many instances the threat of collapse is over looked and simply ignored, in some cases cracks are raked out and repointed but if further movement was to occur the already compromised lintel could in theory collapse bringing the masonry above it crashing down as well.
Lintel Failure often occurs upon the removal of hardwood windows that were originally designed to bear a substantial load without distorting and are replaced with standard uPVC windows which are non-load bearing allowing the lintel to drop or bow causing sagging of the lintel which is shown by the diagonal stepped cracking.
Traditional methods are to remove the lintel and rebuild it, this is an intrusive method of repair and a slow process typically taking around a day to properly remove and replace a lintel.
Lintels can now be repaired using the Twistfix Helical System by using their Bed Joint Reinforcement which effectively creates a new lintel within the existing masonry by remove the mortar within two bed joints above the lintel and inserting helical rods encompassed in grout to create a load bearing lintel which spreads the structural loads across the length of the bars preventing further sagging of the lintel.
With the patented Twistfix 9mm CD helical tie we are able to install 450mm long ties vertically through the masonry in the lintel and pin it into the masonry above. This method is a vast improvement on previous pinning methods which often required 16mm holes drilled through the lintel. We can now install these ties through just 6 or 7mm pilot holes.
This type of repair is a fast and effective method of repair which has been tried and tested with BRE approval. Newman’s can guarantee this type of repair for ten years as we are a member of IGL insurance which covers the consumer in the event that we cease trading.