GENERAL BUILDING ENGINEERING

WOODEN ROOF STRUCTURES

The roof as a building structure consists of a covering constituting an

insulating layer and a skeleton bearing this cover.

Beams, squares and logs connected together in the right way with

carpentry joints fixed with screws, yokes and nails - as a whole they form a

roof truss. [1]

Roof components source:wikipedia.org

ROOF STRUCTURE

The mansard roof structure in Haczów. [4]

TYPES OF ROOF STRUCTURES

The collar beams are the easiest to make and adapt their construction to buildings with the most complex horizontalprojections. All performances, roof windows of attic living spaces, roof projections are not a problem.

Used in buildings, whose span between external walls is in the range of 5.0 to 16.0 m and more, depending on the numberof stool walls and roof slopes.

It is used to connect the rafters in the ridge to the oblique contact and the backrest with the notches on the purlins. Everysecond or third pair of rafters are stiffened with claws. We anchor the rafters to the purlins with one long or two smaller nailsnails. If the ceiling is fireproof, the anchor should be anchored to the ceiling with bolts every 2.0 - 3.0 m, and on woodenfloors connect them with ceiling beams. [1]

Collar beam [15]

COLLAR BEAM

Scheme of the roof over a reinforced

concrete or reinforced brick ceiling. [1]

Scheme of the truss with sloping stool

wall. [1]

Scheme of a mansard roof with an

ordinary stool wall. [1]

SINGLE SIDED ROOF

Scheme of full girders with purlin-and-tick system. [1]

• with two stool walls

• with three stool walls

Scheme of a full truss of a flat roof with a purlin-and-tick system.

[1]

GABLE ROOF

Diagram of a full truss of a mansard roof with a purlin-and-tick

system. [1]

The construction of the mansard roof. [13]

Roofs with a rafter-beam structure are used with spans up to 6 m between theexternal walls of the building and the angle of inclination of roof slopes from 31 °to 56 °. The length of the rafters, depending on the span and angle of the roofslope, can reach up to 5 m. For roofs with a low inclination angle, patches,especially formwork under roofing, provide sufficient stiffening in the longitudinaldirection. Stiffening wind braces are used at steep roofs.

In the roof ridge, rafters are usually joined with traditional fixing, also rafters withceiling beams are connected with a frontal front joint with a dowel pin. Lesslabor-consuming and sufficient is the end-head connector without a spigot,concentrated with a nail.

Gable roofs [11][13]

GABLE ROOF

With larger spans between the outer walls of the building, the cross-section of the rafters is too large to be stiffenough. With a range of 5.0 - 7.5 m, the system is reinforced with unsupported failures.

The leeks are usually added on one side of each pair of rafters and joined with nails, dividing them in a 2: 1ratio, its length should not exceed 3.5 m, at a height of min. 1.8 m due to the comfort of any attic.

At the refractory ceilings, the rafters are based on the masonry so that they can transfer the expansion forcesand resist the tearing forces caused by the wind.

For spans of 7.0 - 9.0 m, the mayflies are too long and are subject to buckling. In this case, the hubbubsupports are supported in the middle of the roof span with the stool walls - a rafter-collar configuration with adeadly supported collar. [1]

Gable roof [16]

GABLE ROOF

[1]

GABLE ROOF – HISTORIC STRUCTURES

GABLE ROOF – HISTORIC STRUCTURES

[1]

GABLE ROOF – HISTORIC STRUCTURES

[1]

[1]

GABLE ROOF – HISTORIC STRUCTURES

[1] mgr inż. F. Kopkowicz, Ciesielstwo Polskie, Arkady Warszawa, 1958

[2] doc. Mgr inż. W. Michniewicz, Konstrukcje drewniane, Arkady, Warszawa 1958

[3] A. Replewicz, K. Regulska, Dachy- geometria i konstrukcja, Wydawnictwo Politechniki Częstochowskiej, 2004

[4] Karta Oceny Stanu Technicznego, inż. P. Foryś, Lublin 2018

[5] jakbudowac.pl

[6] punta.com.pl

[7] dachy.info.pl

[8] sprzedajemy.pl

[9] lech-bud.org

[10] vidaron.pl

[11] fachowy.dekarz.pl

[12] e-dach.pl

[13] muratordom.pl

[14] infoladnydom.pl

[15] phd.pl

[16] hatek.com.pl

Help in collecting materials: Eng. Weronika Kendzierawska

Preparation of the lecture: MSc. Eng. Bartosz Szostak

BIBLIOGRAPHY

This publication reflects the views only of the author, and the Commission cannot be

held responsible for any use which may be made of the information contained therein.

This publication has been funded within support from the European Commission.

Free copy.

Project "SURE - Sustainable Urban Rehabilitation in Europe"

implemented in frames of Erasmus+ Programme

Key Action 2: Strategic Partnership Projects

Agreement n° 2016-1-PL01-KA203-026232