Masonry Repair Strategies
Masonry may deteriorate, delaminate and fail for a variety of reasons. Most of these problems can be overcome by using various combinations of Helifix remedial ties and masonry reinforcement products and techniques.
Helifix products are able to provide secure, lasting connections in all forms of brick, blocks, concrete, stone, timber and traditional local building materials, and have proven to be fully effective in virtually every type of masonry structure from medieval churches to modern tower blocks, from bridges and tunnels to all forms of housing.
The illustration drawn below shows a typical two-storey Victorian property of solid wall construction with a later cavity wall extension.
Highlighted are some of the most commonly occurring structural faults that affect every type of commercial and residential property of all ages and construction. In conjunction with the Helibeam System other products are able to remedy specific problems. These are installed externally in the vast majority of situations leaving buildings visibly unimpaired and causing negligible disruption to their occupants.
Clearly there are other situations which are not shown here such as failed parapet walls, separated cornices, blown render and many more besides. Using various combinations of Helifix ties, fixings and reinforcing rods virtually any situation can be dealt with so do not hesitate to contact us if you have a particular problem which is not covered here.
1. Reconnecting Solid Internal Walls with External Walls
CemTies are installed simultaneously with HeliBond MM3 grout into angled clearance holes drilled, to the required depth, through the external wall and into the internal wall.
References: CemTie Product Detail, Masonry Repair Details for Reconnecting Separated Walls.
3. Repair of Bay Windows
Twin HeliBars are bonded into a predetermined cut slot around the bay above the window with the ends embedded in the front elevation. BowTies are driven into the joist ends via clearance holes in the masonry and low level cracks are stitched with single HeliBars.
References: BowTie Product Detail, Repair Details for Restraining Bowed Walls.
5. Reconnecting Internal Walls with External Walls
Predetermined slots on the internal wall are channelled out to the specified length right into the corner. Angled holes of 12mm diameter are drilled from the corner into the external wall. Single lengths of HeliBar are bent to shape with the angled end bonded into the hole with HeliFix resin or HeliBond grout and the remainder HeliBond grouted into the internal wall.
References: HeliBar Product Detail, Repair Details for Reconnecting Separated Walls.
7. Crack Stitching
Lengths of HeliBar extending 500mm either side of the crack are bonded into cut slots, normal the mortar beds, with HeliBond or HeliFix resin. Where cracks are less than 500mm from an external corner or an opening, at least 100mm should be bent round the corner and bonded into the return wall or bent and fixed into the reveal, avoiding any DPC membrane.
References: Crack Stitching, Repair Details for Stitching Cracks.
9. Creating Masonry Beams
The Helibeam System uses parallel lengths of HeliBar reinforcing bonded into predetermined cut slots (normally the mortar beds) with HeliBond grout to form deep masonry beams which distribute the building loads.
A) shows a beam resisting the horizontal displacement of a bowing wall. Due to the internal stairwell BowTies cannot be used as there are no joists at this point.
B) shows a beam resisting vertical loads to prevent building subsidence.
References: Helibeam System, HeliBond Grout Product Detail, Repair Details for Creating Load Bearing Masonry Beams.
12. Replacing cavity wall ties
DryFix wall ties are power driven directly into both leaves, via a small pilot hole, typically 5mm diameter.
OR
RetroTies are driven into a 5mm to 6mm pilot hole in the far leaf, via a clearance hole in the near leaf into which they are resin bonded.
OR
ResiTies are resin bonded into a 10mm hole in both leaves.
References: DryFix Product Detail, RetroTie Product Detail, ResiTie Product Detail, Repair Details for Replacing Failed or Omitted Wall ties.
2. Stabilising Bowed Walls into Joist Ends
BowTies are inserted through a clearance hole in the masonry and power driven directly into the joist end before bonding with resin into the masonry.
References: BowTie Product Detail, Repair Details for Restraining Bowed Walls.
4. Repairing Separated Masonry
DryFix wall ties or CemTies, depending on the depth of the solid masonry wall, are installed directly into the brick leaves. DryFix ties are power driven directly into the wall via small pilot holes, while CemTies and HeliBond grout are installed into clearance holes drilled through the near leaf and at least 75mm into the far leaf. The density of the ties, DryFix or CemTie, will depend upon the degree and cause of separation, the material and the condition of the masonry overall.
References: CemTie Product Detail, Repair Details for Stabilising Deep Solid Walls.
6. Repairing Brick Arch Lintels
Parallel lengths of HeliBar rod are bonded into the specified cut slots directly above the existing lintel. Angled CemTies or DryFix ties are installed through the lintel and into the masonry above the lower HeliBars.
References: Helibeam System, CemTie Product Detail, DryFix Product Detail.
8. Stabilising Bowed Walls into Joist Sides
BowTies are inserted through clearance holes in the masonry and are power driven through the first and second joist (and third, if required) before the outer end is bonded into the masonry with resin.
References: BowTie Product Detail, Repair Details for Restraining Bowed Walls.
10. Creating Movement Joints
A 400mm HeliBar is installed across the joint, as with cracks, but is only bonded at one end. The other end is allowed to move freely by inserting it into a sleeve which is then bonded into the masonry.
References: HeliBar Product Detail, Repair Details for Creating Movement Joints.
11. Stabilising Failed Masonry Above Openings
Parallel lengths of HeliBar are bonded into the specified cut slots above the existing lintel.
References: HeliBar Product Detail, Repair Details for Creating Load Bearing Masonry Beams.
13. Ceiling Joist Pinning
DryFix ties are driven at an angle through the joist and into the masonry via small pilot holes.
References: DryFix Product Detail.
