March 1987 Table of Contents

Features
Blasting Ledge

A veteran blasting contractor tells how ledge is efficiently removed using new technology and keen judgment. Read more

Clean Fill Wanted

Working on filled sites is risky business, as witnessed by this collection of case studies. Careful site investigations are in order. Read more

Concrete Admixtures

Superplasticizers, air-entraining cement, accelerators, and retarders can make concrete perform to meet a host of special conditions. Read more

Floating Slabs for Unheated Buildings

A thickened-edge slab on a gravel bed can make an economical and durable foundation for a garage or vacation home—even in cold climates, if you follow these prescriptions. Read more

Foundations: Structural Basics

In the first of a three-part series on structural basics, designer Paul Hanke lays out the fundamentals of engineering residential foundations. Read more

Leakproof Basements

Exotic and costly materials are not needed to make a leakproof basement—just good sense and careful workmanship. Read more

Son of Ultrathin Slabs

Since Harris’s last report on these innovative slabs in July of ‘85, several have been put to the test, and so far look pretty good... Read more

Letters
Q&A
On the House Stopping Nail Pops

Q. A house we recently completed has a lot of nail popping—in about 30 places—in the drywall on the cathedral ceiling. Most of the popping has taken place near where the ceiling meets the walls. The cathedral ceiling is framed with 2x10 rafters with one-inch, foilfaced foam insulation between the rafters and the 1/2-inch drywall. The drywall was attached with screws, but I have reason to believe some of them were driven home with a hammer. What is causing the nail popping and how can I prevent it in the future? Read more

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