Conventionally Built 3 & 4 Season Additions in Southeastern Wisconsin

Check out Millennium Windows and Sunrooms LLC’s conventionally built 3 and 4 season additions available in Southeastern Milwaukee! Call 262-364-7655 today!

Millennium Windows and Sunrooms LLC designs and constructs traditionally built sunrooms. These rooms are stick-built and designed with 2×4 or 2×6 construction. Our team will work with you from design to completion to ensure your exact specifications are met. We do not use fiberglass insulation. Instead, we use spray foam insulation between the studs. This ensures all spaces are filled in, preventing air from escaping. Spray foam insulation is significantly more efficient.

We also install moisture-proof subfloors which are specifically engineered to resist water. This means your floors won’t experience warping, swelling or delamination. Your sunroom flooring will remain smooth, flat and quiet.

Increase the size of your home with a year-round sunroom addition from Millennium Windows and Sunrooms. We will work within your budget to determine the best plan for your needs and desires. Every aspect of your room is constructed to high standards and to seamlessly blend in with your existing home.

Four Season Patio Enclosure

Enjoy the outside year-round with a four-season patio enclosure built by Millennium Windows and Sunrooms. Each enclosure is manufactured with thermal breaks throughout and insulated double-pane glass (commonly known as double glazing) so you can warm and cool your room cost-effectively. No matter the weather outside, you can feel comfortable in your four-season patio enclosure.

Three Season Patio Enclosure

A three-season patio enclosure is less expensive and allows you to enjoy the room from spring through fall. Three-season rooms can be usable in the winter when insulated and contain a heat source. Consider 4 Track Window Systems for these rooms if occasional use during the winter is desired. You can customize your airflow and comfort all year round.


Are you looking for some extra space in your home? Whether you want to expand on an existing room, or add a new room entirely, Millennium Windows and Sunrooms can help! We’ve been building beautifully constructed room additions to houses in the Southeastern Wisconsin area for over 20 years. When you add more space to your home, the possibilities are endless. You can make room for new family members or get that home office you’ve been dreaming of, all while increasing the market value of your home!

Here’s what Millennium Windows and Sunrooms’ professional designers, installers and skilled tradesmen can do:

Turn areas into livable spaces, in order to utilize all the space in your home. Extend your house by adding rooms. Whether you want a spare bedroom or a new entertainment space, we’ve got you covered!

Upgrade a room to fully enclose your hot tub or spa

Soundproof rooms – particularly bedrooms

Work with a contractor of your choice to upgrade HVAC systems as part of your custom room addition

As you can see, there’s no shortage of options for custom room additions by Millennium Windows and Sunrooms. Call 262-364-7655 today and tell us your dream plan! We’ll make it happen.

When we work to complete your conventionally built 3 or 4 season addition, we’ll make sure to keep all of these factors in mind:


Site Survey

We’ll conduct a full site survey of your home’s exterior as well as the surrounding issues, to uncover any potential problems and avoid unpleasant surprises.


We can custom design and build you a beautiful addition out of any type of wood you would like, as well as using some of the finest materials on the market today to ensure lasting beauty while almost eliminating any yearly maintenance.


Millennium Windows and Sunrooms takes the time to create a custom design for each conventionally built 3 or 4 season addition we build. We’ll make sure your new addition fits in perfectly with your home’s exterior and yard decor. We will create a 3D rendering provided with our free estimates. With no shortage of options, we guarantee you’ll find exactly what you’re looking for.

Building Codes

We’re very familiar with Southeastern Wisconsin’s county building codes, we will take care of applying for building and zoning permits, attend hearings & board meetings for association approval and work with inspectors on any changes needed.

Years of stress-free enjoyment

We want to make this a long-term relationship. Count on us for quality materials and expert craftsmanship. We would love to assist you in future building projects. Call 262-364-7655 to make your home improvement dreams a reality!

Call 262-364-7655 today to get started on completing your dream home!

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