{"id":15772,"date":"2026-03-04T13:35:01","date_gmt":"2026-03-04T13:35:01","guid":{"rendered":"https:\/\/www.solusio.be\/why-do-i-have-saltpeter-on-my-walls-these-are-the-causes-and-solutions\/"},"modified":"2026-03-04T13:35:30","modified_gmt":"2026-03-04T13:35:30","slug":"why-do-i-have-saltpeter-on-my-walls-these-are-the-causes-and-solutions","status":"publish","type":"post","link":"https:\/\/www.solusio.be\/en\/why-do-i-have-saltpeter-on-my-walls-these-are-the-causes-and-solutions\/","title":{"rendered":"Why do I have saltpeter on my walls? These are the causes and solutions"},"content":{"rendered":"

[vc_row kd_background_overlay=”default” kd_background_image_position=”vc_row-bg-position-top”][vc_column][vc_column_text]Do you see white, powdery patches appearing on your wall? Or does it look like salt crystals are growing out of the plasterwork? Then you are likely dealing with saltpeter. <\/strong>. It looks harmless, but it is almost always a clear signal of an underlying moisture problem.
\nWhere does that saltpeter on the walls come from? And more importantly, how do you combat that annoying white deposit?[\/vc_column_text][vc_empty_space][\/vc_column][\/vc_row][vc_row content_placement=”middle” kd_background_overlay=”gray-color” kd_background_image_position=”vc_row-bg-position-top” css=”.vc_custom_1719408216266{margin-bottom: 50px !important;border-bottom-width: 4px !important;padding-top: 25px !important;padding-right: 50px !important;padding-bottom: 25px !important;padding-left: 50px !important;background-color: #f7f7f7 !important;background-position: center !important;background-repeat: no-repeat !important;background-size: cover !important;border-bottom-color: #8dc63f !important;border-bottom-style: solid !important;}”][vc_column]

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Need Moisture Control in your Home? Contact Us! <\/h2>

Make a No-Obligation Appointment for a Free Site Visit<\/p><\/div>\n <\/div>\n

Contact<\/span><\/a><\/div>\n <\/div>\n <\/div>[\/vc_column][\/vc_row][vc_row kd_background_overlay=”default” kd_background_image_position=”vc_row-bg-position-top”][vc_column][vc_column_text]<\/p>\n

What exactly is saltpeter?<\/h2>\n

Saltpeter is not a mold, but a salt efflorescence. It occurs when moisture in the wall carries soluble salts to the surface. When the moisture in the walls evaporates, those salts remain behind on top of the bricks or the plaster. They form white crystals that have a powdery appearance. <\/p>\n

Saltpeter often occurs on basement walls, ground-floor interior walls, and generally in older homes, but it can basically arise anywhere moisture is present in the wall. Important to know: saltpeter is not a cause, but a consequence. The real problem is always moisture.<\/p>\n

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How does saltpeter develop?<\/h2>\n

To understand why saltpeter appears, you first need to understand how moisture behaves in walls. Walls are porous. This means that bricks are full of small openings through which moisture can penetrate. Bricks can pull up water like a sponge. <\/p>\n

When water moves through the wall in this way, it dissolves the salts naturally present in bricks or mortar. It can also happen that the water carries salts from the ground and brings them into your bricks. Because we heat our rooms, that moisture eventually evaporates. The salts then remain behind as white spots on the walls.<\/p>\n

[\/vc_column_text][vc_empty_space][\/vc_column][\/vc_row][vc_row content_placement=”middle” kd_background_overlay=”gray-color” kd_background_image_position=”vc_row-bg-position-top” css=”.vc_custom_1673366048013{margin-bottom: 50px !important;border-bottom-width: 4px !important;padding-top: 25px !important;padding-right: 50px !important;padding-bottom: 25px !important;padding-left: 50px !important;background-color: #f7f7f7 !important;background-position: center !important;background-repeat: no-repeat !important;background-size: cover !important;border-bottom-color: #8dc63f !important;border-bottom-style: solid !important;}”][vc_column]

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Need Moisture Control in your Home? Contact Us! <\/h2>

Make a No-Obligation Appointment for a Free Site Visit<\/p><\/div>\n <\/div>\n

Contact<\/span><\/a><\/div>\n <\/div>\n <\/div>[\/vc_column][\/vc_row][vc_row kd_background_overlay=”default” kd_background_image_position=”vc_row-bg-position-top”][vc_column][vc_column_text]<\/p>\n

The main causes of saltpeter on walls<\/h2>\n

1. Rising damp<\/h3>\n

The most important cause of saltpeter is rising damp<\/strong>. This is ground moisture that pulls up into the walls via the foundation. Normally this should not happen, because every home is theoretically equipped with a damp-proof course that stops moisture. However, in older homes, this is often missing or the layer has become damaged. <\/p>\n

Typical characteristics of rising damp:<\/strong><\/p>\n