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The Shabbos Weekly
Halachos Series on Hilchos Shabbos

shabbos candles

Published by
Pirchei Shoshanim

A Project of
The Shema Yisrael Torah Network

Based on the Shiurim Given by

Rabbi Dovid
Ostroff, shlita

developed from the Chabura of the
Pirchei Shoshanim Shulchan Aruch Learning Project

These Halachos were shown by Rabbi Ostroff to
HaGaon HaRav Moshe Sternbuch, shlita



Questions for the Week of Parshas Shelach
Parshas Beha'aloscha (Chutz La'aretz)

May one unblock a blocked sink?

The question is whether unblocking a blocked sink or toilet involves the melacha of Boneh – constructing.

The gemora in Kesubos 60a deals with cleaning a gutter filled with dirt on Shabbos and the Rif learns that it involves a biblical violation.

Rav Shlomo Zalman Auerbach ztz”l says [1] that this does not mean that a blocked sink shares the same status. We can understand that the Rif (and gemora) refer to a gutter dug into the surface of the ground, which when blocked with weeds, dirt etc. requires to be dug again, and until then it partially loses its status as a gutter.

A blocked pipe (drain) is a pipe that needs to be unblocked.

I don’t understand, but it needs to be unblocked.

Indeed yes, but compare it to a blocked drinking-straw. You’re drinking chocolate milk and a piece of cocoa gets stuck in the straw. Would you say that forcing the cocoa out the straw is a tikun – repairing? Rav Shlomo Zalman Auerbach thought not, and added that even though the pipes may be buried in the ground, which compounds the problem, [2] a blocked pipe is sometimes unblocked by forcing water through the pipe, which is a normal way to use a sink, and therefore using a plunger to force the blockage is no different.

But still it cannot be used without unblocking?

The Rav said that it should be compared to a dirty window. One cannot see through a dirty window and yet cleaning it on Shabbos (in a permitted manner) will not be Boneh, being that the window is not broken.

What about a porch drain?

A porch drain that is hewed into the ground is different because dirt and debris are batel to the drain, similar to the natural gutter mentioned above. If the porch drain is a pipe it may be unblocked. Some opinions say that if the porch drain is blocked with sticky mud that must be scraped to unblock the pipe, the pipe is ‘broken’ and is forbidden to be unblocked on Shabbos.

To summarize:

  • a blocked sink or toilet may be unblocked on Shabbos.
  • Some say that a blocked drain pipe from a porch blocked with hard mud etc. may not be unblocked on Shabbos. [3]
  • A blocked drain pipe from a porch blocked with leaves and food etc, may be unblocked on Shabbos.

 Is this p’sak accepted by all?

No, it is not. Rav Moshe Feinstein ztz”l [4] discussed three situations.

1. A sink that gets blocked regularly may be unblocked with a plunger because it is not considered broken.

2. If the sink does not get blocked often and water trickles though the blockage, unblocking is a slight repair and a plunger may not be used. It may be unblocked in an irregular manner.

3. If a sink is totally blocked it may not be unblocked on Shabbos, as this is repairing, but when very necessary one may instruct a gentile.

One should ask one’s rav for a final ruling.

Certain doors have locks that have bolts that go into the floor. The hole is blocked and one cannot lock the door, may one clean the hole?

A marble in the hole may be removed; sand and dirt in the hole may not be removed. A marble or pebble is not a natural part of the floor and its removal is not repairing the floor. Sand and dirt is part of the floor and removing sand is digging a hole. [5]

May one remove storm windows at the onset of summer?

Even though storm windows ride a railing and are not attached to the frame, removing or replacing them is an issur d’oraisso of Boneh, as they are regarded as part of the building. [6]

A picture fell off the wall, may one put it back?

Firstly, expensive pictures are muktze and may not be handled. [7] Secondly, we must decide whether it is considered adding to the wall/building and is it boneh or not.

The Chazon Ish writes that something hung on the wall that is easy to remove and is removed, may be hung on Shabbos. A plain clock is not nailed to the wall and is removed to change the battery and therefore one may place it on a hook on the wall on Shabbos.

The same applies to a picture hung in a way that it can be removed easily. [8]

On the other hand, a rubber pipe attached to the tap above the sink that fell off may not be reattached to the tap. [9] The rubber pipe is intended to be a permanent fixture and attaching it to the tap is Boneh.

[1] Binyan Shabbos pgs 18, 303.

[2] An item attached to the ground is subject to the restrictions of Boneh, unlike keilim.

[3] See the Binyan Shabbos.

[4] Igross Moshe Orach Chaim vol. IV simon 40:9.

[5] Binyan Shabbos pg 18.

[6] See Bi’ur Halacha simon 313:1 ã"ä åìà.

[7] SS”K 20:22.

[8] SS”K 23:39 footnote 123.

[9] Binyan Shabbos pg 306.


Food for Thought

May one stick a rubber suction hook onto a wall?

What about attaching a set of hooks to the top of the door?

A towel hangs from a pipe affixed between wall brackets. May one remove the pipe on Shabbos?

Is it permitted to attach the needle to a syringe on Shabbos?

Vort on the Parsha

“They are our bread”, Rashi explains we can eat them like bread. The K’sav Sofer explains that if we fight for the sake of Hashem – a milchemes mitzvah – it is like eating bread, which is a necessity, Hashem will fight our wars. But if we fight wars to take revenge, we will not overcome the enemy.

This week’s Shabat Shiur sponsored by:
Gary Arenson of
Ergo-Therapy Solutions in South Africa.
Ergo Therapeutic Office Chairs


For a printed version, click here.



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Note:  The purpose of this series is intended solely for the clarification of the topics discussed and not to render halachic decisions. It is intended to heighten everyone's awareness of important practical questions which do arise on this topic.  One must consult with a proper halachic authority in order to receive p'sak.