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Flood-proof* basement windows

ACO Therm® 3.0 flood proof*
For every geographical location and hazard situation

Only those who feel safe within their four walls can speak of real living quality.

In recent years, weather extremes such as heavy rainfall have increased. Basement areas are at risk from both rising groundwater and surface water. A 24-hour flood-proof* version of the new ACO Therm® 3.0 reveal window is available for use in flood-prone areas.

The basement window features reinforced panes, a watertight frame seal, additional locking points and mushroom-shaped locking pins that provide additional burglary protection. The outer pane is made of laminated safety glass and is sealed in the sash. The living room appearance of the window is completely preserved.

The flood-proof* basement window should be installed together with the pressurised water-proof light shaft from ACO, it cannot replace it. The basement window cannot be part of a permanent building seal in accordance with DIN 18533. It is tested for installation in waterproof concrete when the installation instructions are followed exactly.

Tested by the ift Rosenheim

The ACO Therm® reveal basement window flood-proof is 24-hour watertight and flood-resistant in accordance with the ift Rosenheim guideline FE-07/01 "Flood-resistant windows and doors". Each individual ACO Therm® reveal cellar window flood-proof is subjected to a leak test during production and then sealed until it is put into operation.

Care instructions and maintenance certificate

Installing the ACO Therm® reveal window flood-proof* is the right decision for an excellent quality product, because by installing it you protect your cellar! If the installation instructions and product information are observed, it is watertight in accordance with the ift guideline FE-07/1 "Flood-resistant windows and doors", October 2005 edition*. The ACO Therm® reveal window flood-proof* is not part of a permanent structural waterproofing system according to DIN 18533 and cannot be permanently included in the waterproofing layer. It is tested for installation in waterproof concrete.

The reveal window flood-proof is watertight up to at least 1.0 metre on delivery and flood-resistant up to 1.4 metres, measured at the lower edge of the window. Each window is tested for tightness after production, the test is documented by means of the serial number and the window sash is sealed. Regular maintenance is essential to maintain the tightness.

The ACO Therm® 3.0 HWD-S plus
Flood-proof* basement window for retrofitting

When basements are suddenly flooded due to heavy rainfall, this is flood damage that is often not covered by standard homeowners and contents insurance. A basement in an existing building can be retrofitted with the flood-proof* reveal window HWD-S plus. The HWD-S plus is industrially manufactured and supplied complete with collar.

Installation of the renovation window

First, the old window is removed and the reveal is sealed watertight to the outer wall coating with 2K thick coating *** The HWD frame is wedged into the wall opening and screwed all around with wall anchors. Then the adhesive is applied in several beads to the coated reveal and the HWD-S plus sleeve is pressed on all around. The cavity around the window is filled with ACO special filler. The joints on the inside are sealed. We recommend that the installation be carried out by an ACO service partner or a specialist company trained by ACO using the accessories and material offered and approved. Otherwise, neither a warranty for the construction connection nor for the window itself can be assumed.


Notes: The ACO Therm® high-water-tight reveal window* does not replace the pressurised water-tight light shaft and cannot be part of a permanent structural waterproofing system in accordance with DIN 18533. It has been tested for installation in waterproof concrete. The installation instructions and product information must be observed! The user must check the products for their suitability for the intended application. To maintain the watertightness/flood resistance, the window must be serviced by an ACO service partner once a year and after every flood event.

UW-value (for window size 123 x 148 cm) calculated with WinIso2D Professional 7.95 according to EN 10077-2

* Test report 14-002562-PR01 available at

** Test report 15-001619-PR01, available at

*** Building connection tested by MFPA Leipzig, test report PB 5.1/14-370-1 available at