For Owners

Understanding your terrace's waterproofing condition — and your responsibilities as an owner in a shared building — is the starting point for protecting your property.

Individual Owners

Your terrace and the unit below

In a residential building, each terrace or balcony is typically the exclusive use area of the unit it belongs to — but its waterproofing condition affects the unit directly below. A failed membrane on your terrace does not just create a problem for you. It creates a problem for your neighbor.

This is particularly relevant in co-investment scenarios, where the unit above and the unit below may be owned by different investors, occupied by different tenants, or managed by different property managers. When water appears on the ceiling of floor 11 and the source is the terrace of floor 12, establishing responsibility clearly — and resolving it quickly — requires documentation.

A diagnostic assessment that confirms whether your terrace membrane is functional or has failed gives you that documentation. If the membrane is intact, you have evidence. If it has failed, you have a clear path to resolution.

Apartment owner reviewing terrace condition with a waterproofing specialist in a Santiago residential building
Common Situations

What owners typically encounter

I have water stains on my ceiling and my neighbor above has a terrace. What should I do?
The first step is to document the damage — photographs with date and time stamps are useful. Then, contact the building administration to formally notify them of the situation. A water tightness test on the terrace above is the standard way to determine whether the membrane is the source. This test should be performed before any repair work begins, as it establishes the baseline condition.
My terrace membrane appears to be in poor condition. Do I need to replace it even if there are no visible leaks below?
Visual deterioration of a membrane — cracking, blistering, separation at edges — is an indicator of reduced waterproofing capacity, even if active leaks have not yet appeared below. Water infiltration through a compromised membrane is a gradual process. By the time visible damage appears on the ceiling below, the moisture has often been present in the structure for an extended period. A water tightness test will confirm whether the membrane is still performing its function.
The building was recently constructed. Is waterproofing still a concern?
New construction does not guarantee a correctly applied membrane. Application errors — insufficient coverage, incorrect product for the surface, application under adverse weather conditions — can result in membrane failure within the first few years of a building's life. If you are experiencing infiltration symptoms in a relatively new building, a diagnostic assessment will determine whether the membrane was applied correctly in the first place.
I am selling my apartment. Should I address the terrace waterproofing before listing?
A documented waterproofing assessment — whether it confirms the membrane is in good condition or records that it has been replaced and verified — is useful information for a buyer. It removes a potential source of uncertainty from the transaction and avoids post-sale disputes related to water damage that may have been present but not disclosed.
The building administration wants to address waterproofing across multiple floors. How does that work?
We work with building administrations to coordinate multi-unit programs. This typically involves a phased assessment of all affected terraces, followed by a prioritized work schedule based on urgency. Building committees receive a single point of contact and consolidated documentation for all units addressed. This approach is more efficient for the building than handling each unit as a separate incident.
Building committee members reviewing waterproofing documentation and project plans in a meeting room
Building Committees

Addressing waterproofing at the building level

Building committees and administrations often face recurring water infiltration claims from multiple owners across different floors. In many cases, these incidents are related — water entering through multiple failed membranes on different levels of the same building.

A systematic approach — assessing all terraces and balconies, identifying those that require intervention, and addressing them in a coordinated program — is typically more effective than responding to each incident individually as it arises.

Consolidated documentation for building records and assemblies
Coordinated scheduling reduces total disruption to residents
Consistent materials across all treated units in the building
Written guarantee per unit, held by each individual owner
Contact for Building Programs

Questions about your specific situation?

We can discuss the details of your building, your unit, and what a diagnostic assessment would involve. Contact us directly.