Per Guide

1New in the manual

Calling a Pro

Signs old attic insulation should come out

Discover the signs that tell you when attic insulation removal is necessary and when you can simply add a new layer over the top of the old material.

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October 22, 2026 6 min. reading

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  Calling a Pro

  Which home projects need a building permit and which do not

  Find out exactly what your city building department does, which home projects require a permit, and the small repairs you can do without permission.

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  Adding On

  How an addition roof joins the existing roofline

  Learn how a roof extension joins your existing roofline through a shed tie in, a gable with valleys, or a low slope link to prevent leaks.

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  Adding On

  How a room addition ties into the house you already have

  Building an extension on a house requires linking the new foundations, load bearing walls and mechanical systems directly to your existing structure.

1. 5 ways to insulate exposed pipes in cold spaces

   Building Systems 6 min. reading

2. Why ducts in the attic need insulation and how much

   Building Systems 6 min. reading

3. What roof decking does and the signs it needs replacing

   Roof Structure 6 min. reading

4. 9 parts of a roof and what each one does

   Roof Structure 6 min. reading

2Parts of the house

1. Foundations

   How slabs, crawl spaces and basements carry a house, what cracks and settling really mean, and which fixes hold up.

   • What underpinning a house involves and when it is needed
   • Which foundation settling cracks are normal and which are not

2. Walls and Framing

   How studs, headers and beams carry weight, how to tell a load bearing wall from a partition, and what changes when one comes out.

   • What shear walls and hold downs do in a wood frame house
   • How a house is framed from the sill plate to the rafters

3. Insulation and Moisture

   R-values, blown in and batt insulation, vapor barriers, damp walls and the way heat and water move through a house.

   • 6 steps to insulate a crawl space and keep moisture out
   • Does your attic need a vapor barrier

4. Roof Structure

   Rafters, trusses, pitch, decking and ventilation explained, plus the roof shapes you see on American houses and how each one behaves.

   • How roof pitch is measured and what the numbers mean
   • Hip vs gable roof and how each one stands up to high wind

5. Building Systems

   How the heating and cooling, plumbing and electrical systems are laid out inside a house and what each part does.

   • 5 ways to insulate exposed pipes in cold spaces
   • Why ducts in the attic need insulation and how much

6. Adding On

   How a room addition ties into an existing house, from footings and framing to roofline, utilities and inspections.

   • How an addition roof joins the existing roofline
   • How a room addition ties into the house you already have

7. Calling a Pro

   Clear signs that a job needs a structural engineer or licensed tradesperson, and how to prepare for the visit.

   • 8 things a structural engineer checks in a foundation inspection
   • Signs old attic insulation should come out