Structural Reinforcement

Israel runs along the Syrian-African rift, an active fault that crosses the Jordan Valley and the Arava. According to the professional bodies, a magnitude 6 or stronger earthquake occurs in the region on average once every 80 years or so, and the last destructive one was in 1927, which means we are inside the window for the next.

The national reference scenario projects enormous damage to buildings not designed to code, mainly in the ten high-risk cities along the rift. And still, out of roughly 80,000 buildings in Israel that need reinforcement, only about 2.3% have actually been treated. That gap is exactly why reinforcing a building is a necessity, not a luxury.

• The Syrian-African rift: a seismically active zone
• A strong quake on average once every 80 years, the last in 1927
• Roughly 80,000 buildings need reinforcement, about 810,000 apartments
• Only about 2.3% of the buildings have been reinforced to date

The Israeli standard for seismic resistance, IS 413, became binding in construction around 1980. The accepted professional assumption is therefore that any building whose permit was issued before 1 January 1980 does not meet the standard and needs assessment and reinforcement.

IS 413 Part 3 is the standard by which existing buildings are evaluated and reinforced. The most common weak point is an open ground-floor column story, a “soft story,” whose stiffness is below 70% of the floor above it. This is the leading cause of older residential building collapse, and exactly what correct reinforcement design fixes.

• Buildings from before 1980 are presumed non-compliant
• IS 413 Part 3: assessment and reinforcement of existing buildings
• An open column story is the critical weak point
• Buildings from 1980 to 1984 may also require reinforcement

Every reinforcement design starts with an engineering survey performed by a structural engineer. We gather the building file and original plans, expose foundations at several points to check the founding, and run lab tests to learn the true strength of the existing concrete and rebar.

The tests include a Schmidt hammer for concrete uniformity, concrete core drilling for lab strength testing, a cover meter to map the rebar, and chemical tests for corrosion. Only then do we shape a tailored reinforcement scheme and an estimate. A flawed design is more dangerous than no reinforcement: incorrect work can actually weaken the structure.

• Collecting the building file, plans, and a soil report
• Exposing foundations and checking the existing founding
• Schmidt hammer, concrete cores, and rebar mapping with a cover meter
• A report with a recommended scheme and a cost estimate

There is no single correct method, there is the one right for your building, and it follows from the engineering survey. In Israel the common combination is shear walls and a safe-room tower as a global system for horizontal forces, column jacketing and foundation strengthening, with carbon fiber as a targeted complement.

We choose the mix by the concrete condition, the space constraints, and whether the building is occupied, and design a solution that achieves the required resistance efficiently and at the best cost.

• Reinforced-concrete jacketing for columns and walls
• Shear walls continuous from the foundations to the roof
• Steel frames and bracing for a light, fast solution
• Carbon-fiber wrapping for targeted strengthening with no added weight
• Micropiles and foundation strengthening in tight access
• Seismic isolation for critical public buildings

This is where our two core fields meet. A safe-room tower is not only protection, it is built as a continuous reinforced-concrete box that runs down to new foundations, so it acts as a new stiffening core that absorbs horizontal forces. Adding safe rooms in a reinforcement project is usually the building’s main strengthening element.

What this means for you: a single project delivers both a protected space for every apartment and seismic resistance, a double defense against missiles and against an earthquake. On floors without a safe room, we continue at least 70% of the wall perimeter down to the foundations to keep the reinforcing tower continuous.

• A safe-room tower acts as a new stiffening core
• Double defense: protection and seismic resistance in one project
• The 70% rule: wall continuity down to the foundations
• The state incentivizes combining reinforcement and a safe room through grants

The familiar national reinforcement plan has ended, and a new set of tools is in its place. The “Shaked alternative” (Amendment 139 to the Planning and Building Law) and municipal plans under Section 23 allow renewal and reinforcement with building rights, and evacuate-and-rebuild has become the main engine for renewing old buildings.

For buildings without developer viability, a short-track standalone reinforcement route was added under NOP 40/C, and in the high-risk cities there are state grants of up to 100,000 NIS per dwelling for reinforcement, and up to 200,000 NIS when a safe room is combined. We navigate you between the routes and choose the one that fits your building and goals.

• The Shaked alternative and municipal Section 23 plans
• Evacuate-and-rebuild as the main renewal engine
• A short-track standalone reinforcement route under NOP 40/C
• Grants in the high-risk cities, up to 200,000 NIS with a safe room