If the dampness is showing in a property with external ground levels that are higher than the internal floor level, the moisture resident in the external ground is not only a contributing factor for the dampness already identified, but the high ground could also be saturated enough for water to bear against the structure, creating a risk of water ingress also.
Where high ground levels exist, it should be assumed that water ingress is a possibility and so a waterproofing system is required. Where there are no high ground levels a damp proofing solution is required.
if the external ground levels are lower than the internal walls (or if the external ground could be lowered) – a damp proofing system would be the recommended solution (Newton System 800 – Damp Proofing)
if the external ground levels are higher than the internal walls, for example a basement or cellar – a full waterproofing system is required (Newton System 500 – Cavity Drain Waterproofing)
Damp Proofing detail showing Newton System 800 application about external ground level
BS8102 assists in clarifying the most suitable type of waterproofing required for the scenario
In situations where the external ground is higher than the internal floor, we are governed by BS8102:2009 (Code of Practice for The Protection of Structures Against Water from the Ground) BS8102 is a design document used to inform the designer of the various methods of waterproofing available and to assist in the correct specification of those systems.
Principle considerations are listed in BS8102 in order to develop a robust design for protecting a structure against groundwater. The overall general principle is to assess the risk of water reaching the structure and then to select a waterproofing system capable of achieving the required internal environment
With the above in mind comes a word of warning, it is common for people to question why they should have a full waterproofing system if they only have slightly high ground levels and/or there is no running water present at the time. Whilst we understand their reticence, BS8102:2009 states that regardless of conditions at the time of survey, one should consider that water ingress will occur at some time in the future, and also suggests that as well as water within saturated ground we must consider the following as potential sources of water ingress:
fluctuating water tables
the future effects of climate change
temporary pockets of water
perched water tables
burst water mains
The consequences of installing a damp proofing system where a waterproofing system should have been installed can be serious, with a high probability of water ingress and flooding. The resulting consequential loss can be devastating.
We are always delighted to advise on any waterproofing or damp proofing projects, just call us on 01732 360 095 and we will put you straight through to one of our experts or e-mail us on email@example.com . Please click here for a list of Newton Specialist Basement and Damp Proofing Contractors in your area